EPA Report No.:
                                             EPA-AA-CPSb-63-02
                        Technical  Report
                 Exhaust Emissions from In-Use
                  High-Mileage Passenger Cars
              1979 Model Year California Vehicles
                         Alan Lockwood

                         December 1983
                             NOTICE
Technical Reports do not necessarily represent final EPA
decisions or positions.  They are intended to present technical
analysis of issues using data which are currently availaole.
The purpose in the release of such reports is to facilitate the
exchange of technical information and to inform the public of
technical developments which may form the basis for a final EPA
decision, position, or regulatory action.
             U. S.  Environmental Protection Agency
                  Office of Air and Radiation
                   Office  of Mobile Sources
                    Certification  Division
            Certification Policy and Support Branch
                      2565.Plymouth Road
                   Ann Arbor,  Michigan 48105

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 I.    Abstract

      This  report contains an analysis of  the  results of
 Federal Test  Procedure  (FTP) emissions testing of  98 1979 model
 year California vehicles that had accumulated  between 40,UOO
 and 50,000  miles.  The vehicles were procured  from the general
 public and  represented the largest selling models  and engines
 marketed by the aajor domestic manufacturers during the 1979
 model year.   All vehicles were screened for proper use and
 maintenance.  Also, prior to initial emissions testing, minor
 control system disablements and engine parameter maladjustments
 were corrected.  Although some differences exist,  the screening
 criteria and  program protocols were such that  the  test results
 are comparable to present Recall surveillance  testing.
 Following initial testing, the vehicles that failed to meet the
 1979 California standards  (HC = 0.41 g/mi, CO  = 9.0 g/mi, NOx =
 1.5 g/mi) received restorative maintenance and were retested.

      Test  results indicate that the vehicles  tested were
 generally not in compliance with the HC standard.  CO and NOx
 performance was better than HC performance with fewer vehicles
 failing and average levels generally at or near the standard.
 The overall average emission levels for the initial test were
 0.73 g/mi for total hydrocarbon (THC), 0.60 g/mi for nonmethane
 hydrocarbon (NMHC), 8.5 g/mi for CO, and 1.6 g/mi  for NOx.
 None of the manufacturers had average HC (THC or NMHC) levels
 below the 0.41 g/mi standard.  The restorative maintenance was
 successful  in reducing NOx and CO but was less successful in
 reducing HC.  The overall average after-maintenance levels for
 CO and NOx were below the applicable standards while the
 average after-maintenance HC level remained above  the standard.
II.   Introduction

      The Office of Mobile Sources  (QMS) has been examining
various alternative motor vehicle emission compliance programs.
As part of this evaluation the possibility of assessing
compliance based on the performance of properly used and main-
tained light-duty vehicles near the end of their statutory
useful-life (50,000 miles) has been discussed.  To do this type
of compliance assessment, vehicles could, for example, be
tested between 40,000 and 50,000 miles.  To evaluate the impact
of the concept of testing vehicles between 40,000 and 50,000
miles we need to evaluate the effects of this type of program
proposal on the stringency of the emission compliance program,
the causes and potential remedies of noncompliance, and the
cost and associated difficulties in conducting such a high
mileage compliance program.  This report analyzes emission data
generated by a sample of properly used and maintained 1979
model year California vehicles, and discusses how these data
relate to compliance program stringency and noncompliance
remedies.  The analysis of test program costs and implementa-
tion are contained in a separate report entitled "A Summary of
the Procurement Activities of In-Use High Mileage Passenger
Cars (the AESI Small Sample Study)," EPA Report No.
EPA-AA-CPSB-83-07.

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                              -2-

      The stringency of a compliance program is related to the
requirements placed on the manufacturers as a result of the
structure of the compliance program itself.  The current
emission compliance program requires vehicles to be capable of
compliance with the emission standards for their statutory
useful life  (5 years or 50,000 miles for light-duty vehicles).
Although very little testing currently is done between 40,000
and 50,000 miles, properly maintained and used vehicles within
this mileage range should be meeting the emission standards
under the current rules.  Thus, current requirements lead us to
assume that the stringency of the compliance program should be
unaffected by changes in compliance testing mileages.  The data
generated under this testing program will allow us to begin to
evaluate this assumption by measuring the capability of current
vehicles to comply with emission standards between 40,000 to
50,000-miles.

      Having quantified the ability of in-use vehicles to meet
emission standards, we must also examine options to remedy
noncompliance when it occurs.  The noncompliance remedy issue
deals with the ability of the compliance program to effectively
identify emission noncompliance and cause that noncompliance to
be corrected.  To evaluate a manufacturer's ability to remedy
noncompliance, we need to examine the responsiveness of those
vehicles that fail to meet the standards to restorative main-
tenance and the type of restorative maintenance necessary to
remedy the emission noncompliance.  The types of vehicle
failures that are encountered in-use between 40,000 and 50,000
miles and the maintenance necessary to correct these failures
must be considered when evaluating the effectiveness of a com-
pliance program.  For example, certain types of vehicle problems
can be efficiently repaired in the field while others are more
effectively corrected by design changes.  The compliance pro-
gram structure should be such that it can effectively handle
the types of problems encountered most often.

      Two EPA programs currently collect emission data on
in-use vehicles; the present in-use compliance (Recall) program
and the Emission Factors program.  The current Recall program
has authority to determine compliance through 50,000 miles.
However, vehicles are typically tested for compliance at a
lower average mileage.  Few individual vehicles close td 50,000
miles have been tested in the Recall program.  The Emission
Factors program has tested many vehicles in the 40,000 to
50,000-mile range.  However, Emission Factors vehicles are not
screened for proper use and maintenance and are, therefore,
generally ineligible for use in a compliance determination.
(The Clean Air Act relieves the manufacturers of the
responsibility of assuring the emission compliance of vehicles
that are not properly used and maintained.)  Thus, insufficient
data were available to evaluate a high mileage in-use
compliance program.

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                               -3-

      Because the available data on properly used and
maintained  in-use vehicles in  the  40,000-50,000 mile range were
too  limited to adequately address  the necessary issues, a
testing program was  initiated  to gather additional data.  This
report presents the  data from  the  first phase of this
data-gathering process.  Testing of subsequent model year
Federal vehicles is  underway.   In  a future report, all
pertinent high mileage information will be considered to
provide a consolidated analysis.

      This  initial data-gathering  effort was conducted under
contract at the AESi facility  in the Los Angeles area of
California.  The vehicles tested in this first testing phase
were 1979 model year gasoline-fueled light-duty vehicles
certified for sale in California.  1979 model year California
vehicles were selected for testing for this program because
they were equipped with the most current emission control
technology for vehicles that were  old enough to have
accumulated the necessary 40,000 to 50,000 miles at the time
the testing took place.  The actual average test vehicle
mileage for this test program  was  43,806 miles.  The vehicles
were procured from the general  public in Los Angeles and Orange
counties in California.

      All of the vehicles were  screened for proper use and
maintenance and inspected by AESi mechanics.  Vehicles chat had
not received proper maintenance and those with major control
system disablements were rejected  from the program.  Minor
disablements and maladjustment  were corrected prior to the
initial test.  These protocols  were followed so that our test
fleet would represent properly  used and maintained vehicles
including proper engine parameter adjustments.

      The vehicle screening and inspection criteria were
similar to the criteria used in the Recall surveillance
program.   The initial tests performed in this test program are
generally comparable to the Agency's Recall program surveillance
tests.   While in some cases the specific protocols are
different, these differences are not expected to significantly
influence measured average emission performance.  Thus, these
data represent a reasonable measure of manufacturer compliance
at high mileage for these classes of vehicles.

      Each vehicle accepted into the program was tested using
the Federal Test Procedure as outlined in 40 CfR Part 86 Sub-
part B.   Vehicles that did not meet the 1979 California
emission standards of 0.41 g/mi HC, 9.0 g/mi CO, and 1.5 g/mi
NOx were repaired and retested.  The goal of the repair process
was to correct the causes of the emission failures and restore
the vehicles to manufacturer design specification,  hopefully so
that they could meet the standards.  In many instances,
representatives of the various manufacturers aided in the
diagnosis and repair process.

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                               -4-

      The vehicle sample procured and tested for the program  is
shown in Appendix 1.  The sample consisted of vehicles repre-
senting the largest selling model types and engine displace-
ments for each of the three major domestic manufacturers; GM,
Ford, and Chrysler.  Some Mitsubishi vehicles were also included
because they represented a significant portion of Chrysler's
product offering.

      Individual vehicle test  results are shown in Appendix 2.
A brief summary of the test vehicle procurement, inspection,
and maintenance procedures is  contained in Appendix 3.  As
discussed earlier, a detailed  discussion of the vehicle pro-
curement for this program is contained in a separate report.


III.  Test Results

      A.  The 1979 California  HC Standard

      Before beginning the discussion of this program's test
results, a brief discussion of the 1979 California HC standard
is warranted.  The 1979 California HC standard applies to non-
methane HC.  To be in compliance with the 1979 California 0.41
g/mi HC standard a vehicle's total HC level multiplied by the
appropriate Methane Content Correction Factor (MCCFj must be
below the 0.41 g/mi level.  For the 1979 model year, the Cali-
fornia Air Resources Board allowed the use of a general MCCF of
0.89.  In addition, manufacturers were allowed to use alter-
native MCCF's if they could demonstrate that the alternative
MCCF's better represented the  performance of their vehicles.
Therefore, from the standpoint of compliance with the 1979 Cali-
fornia HC standard of 0.41 g/mi, the relevant HC level is the
factored or nonmethane HC level.  The Federal program, however,
uses total HC as the value to compare against the Federal stan-
dard.  Therefore, the total HC level is the level relevant to
the Federal Program.

      For this report parallel calculations were made for total
HC (THC) and mon-methane HC (NMHC).  Pass/Fail rates were also
determined based on both THC and NMHC levels.  For making pass/
fail determinations the THC and NMHC levels were compared to
the 0.41 g/mi standard.

      While much of the discussion in the report will focus on
the THC levels the reader should keep in mind that the manufac-
turers designed,  certified,  and built their 1979 model year
California vehicles to comply with the 0.41 g/mi HC standard by
using emission levels factored by the appropriate MCCF.  The
MCCF's applied to the test data for each engine family tested
are shown in Table 4.

      B. Initial Test Data—Overview

      The discussion of  the test data that follows,  and the
related tables and figures,  concentrate mainly on various
average emission levels.   The nature of the averaging process

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                              -5-

tends, at times/ to obscure some of the detail of the under-
lying data.  To give the reader some feel for the profile and
range of the underlying data, Figures 1 through 4 have been
prepared.  For these figures, the initial test results were
sorted by emission level in ascending order for each pollu-
tant.  These sorted emission levels were then plotted.  Each
point on the plot represents the emission level of one of the
98  initial tests.  The vehicle with the lowest test level is on
the left with levels increasing to the right in ascending
order.  Also plotted in these figures are the applicable
emission standards.  By examining these figures we find that
most of the vehicles have emission levels that are grouped near
the standard (the left and center portions of the curves).
There is also a  second smaller group of vehicles that has
higher and more variable emission levels (portion of the curve
near the right end where the slope begins to increase) .
Finally on the far right of the figures we find a very small
group of vehicles with very high emission levels.

      These figures also allow the reader to graphically
evaluate the total emissions generated by the test fleet.  The
areas shown under the curves representing the emission levels
represent the total amount of each pollutant emitted by the
test fleet.  The areas under the standard lines represent the
total amount of each pollutant allowed by the standards.  The
areas that lie above the emission level curves and below the
standard lines on the left end of each figure represent the
amount by which the passing vehicles were able to better the
standards.   On the right end of each figure where the emission
level curves are above the standard lines (test vehicles failed
to meet the standards)  the areas between the lines represent
the amount of each pollutant that is in excess of that allowed
by the standards.  The differences between the two areas under
the emission level curves and the standard lines represent the
total amounts of pollutant emitted by the test fleet that are
above or below the amounts allowed by the standards.  These
values have been calculated and are shown in Table 1, oelow.

                            Table 1
                        Total Emission*
                         Initial Tests
THC
NMHC
CO
NOx
Number of
Vehicles

   98
   98
   98
   98
  Total
 Amount
Measured

   72
   59
  832
  160
  Total**
  Amount
Allowed by
 Standard

    40
    40
   882
   147
Excess
Amount

  32
  19
 -50
  13
Excess as
 Percent
of Amount
 Allowed

   80
   48
   -6
    9
     * The emission values shown are grams of pollutant emitted
       for each mile traveled by the entire fleet (grams per
       fleet mile).
    ** Total amount allowed = standard x number of vehicles.

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 1.30
 (1.00
,3.50
 0.0
                                -6-

                            Figure 1
               THC Performance  in Ascending Order
                        Initial Test Data
            23
        Vehicles
          Below
         .41 THC
   75
Vehicles
  Above
 .41  THC
                   Vehicles Sequentially Ranked
                             Figure 2
                NMHC Performance in Ascending Order
                         Initial Test  Data
 (4.90
 <4.00
 3. SO
53.00
=2.00
 .1.50
  1.00
 0.30
 0.0
                  41
              Vehicles
                Below
               .41 NMHC
                    57
                 Vehicles
                   Above
                 .41 NMHC
                      25              50
                   Vehicles  Sequentially  Ranked
                                           98

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                                -7-
                              Figure 3
                  CO Performance in Ascending Order
                          Initial Test Data
  SO
  to
  to
 s
 alS
 w

  10

   5
                                             74
                                          Vehicles
                                           Below
                                           9.0 CO
                                                   24
                                                Vehicles
                                                 Above
                                                 9.0 CO
Standard=9.0
                   25              50
                 Vehicles Sequentially Ranked
                                                    75
                                                          98
S.O

4.S

4.0
•4.0
IM
                              Figure 4
                 NOx Performance in Ascending Order
                          Initial Test Data
gl.S
x
 1.0

 0.5

 0.0
       Standard=1.5
                                  64
                               Vehicles
                                Below
                                1.5  NOx
                                              34
                                           Vehicles
                                            Above
                                           1.5 NOx
                    25              50
                  Vehicles Sequentially Ranked
                                            75
                                                               98

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                               -8-

The total amount of pollutant  exceeds  the allowable  amount  for
all pollutants except CO.  THC and NMHC  have the  highest
percentage exceedances of 80 percent and 48 percent
respectively.  The NOx exceedance is lower at  9 percent.

      C.  Initial Test Data—Detail

      Table 2 and Figures 5 through 8  contain  the average
emission levels for each manufacturer  for the  initial emission
tests.  Again, these levels are representative of manufac-
turers' compliance levels for  the particular vehicles tested.
None of the manufacturers had  initial  average  THC or NMHC
levels below the 0.41 g/mi standard.   Only Ford had  an initial
average CO level below the 9.0 g/mi standard.  General Motors
and Chrysler had initial average NOx levels at or below the 1.5
g/mi standard.  THC and NMHC were the  most consistently failed
pollutants with the highest initial overall percent  of standard
average emission level (0.733  g/mi or  179 percent of the stan-
dard for THC and 0.600 g/mi or 146 percent of  the standard  for
NMHC).  The overall initial average CO emission level was below
the standard (8.49 g/mi or 94  percent  of the standard) ana  the
overall initial average NOx level was  slightly above the stan-
dard (1.63 g/mi or 109 percent of the  standard).

      Table 3 shows the pass/fail rates for each manufacturer
for the initial test.  In Table 3 the  number of vehicles that
met the standards for all three pollutants is  shown  in the
"total pass" column.  Separate pass rates were prepared based
on THC and NMHC.  The percentage figures shown are the percen-
tages of each manufacturers' total.  The numbers shown in the
"total failed" columns for each pollutant are  the number of
vehicles failing to meet the California standard for that
pollutant.  Because some vehicles failed to meet the standards
for more than one pollutant the total  of the failed columns
will exceed the total number of vehicles tested.  Again
separate failure rates were prepared for THC and NMHC.  For the
98 vehicles tested in this program, 13 percent (13 vehicles)
met the California standards for all 3 pollutants based on
THC.  Twenty-four percent (24  vehicles) met all 3 standards
based on NMHC.   Figure 9 shows the pass/fail breakdown for all
pollutants and combinations of pollutants.

      The average emission levels and  failure  rates  tor each
engine family tested are shown in Table 4.   When examining  tnis
data the reader must keep in mind that the number of vehicles
tested per engine family varied considerably (only one vehicle
was tested in some families).   The pass/fail rates are shown as
percentages and are particularly susceptible to misinterpreta-
tion if the engine family sample size  is not taken into
consideration.

      Based on THC, General Motors'  engine family 940E2LU
(231-CID V-6)  had the best pass/fail performance with a 50
percent pass rate (Ford engine family  1.6G1X128 also had a 50
percent pass rate but only two vehicles were tested  in that

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                                              Table ^
                                      Average Qnission Levels
                                           initial Test
Manufacturer

GM

Ford

Chrysler

Mitsubishi

All
Number
of Vehicles
54
33
7
4
96
Total
Average
.729
.569
.7^0
2.140
.7^3
Non-Methane*
hC
Average
.593
.446
.629
r.905
.000
CO
Average
9.34
4.3J.
13.33
23.10
ti.49
MOx.
Average
1.52
l.bl
l.Jb
1.90
1.63
1979 California Standards:

         HC  =  .41  (Non-Methane;*
         CO  = 9.0
         NOx =1.5

Average Vehicle Mileage:

         43,806 miles
*Non-Methane HC = Total HC x Methane Content Correction Factor.

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  2.2

  2.0

  1.8

  1.6
ul.O
o
  0.6

  0.4

  0.2

  0.0
                     -10-

                   Figure 5
              Average THC Levels
               Initial Test Data
.729
.569
.740
2.14
                                      .733
                                      THC Level:  0.41 g/mi
          CM     FORO   CHRT   MITSUB   RLL
 2.2

 2.0

 1.8
UJ J \l
a
= 1.0
|0.8
ui
£0.6

 0.4

 0.2

 0.0
                   Figure 6
              Average NMHC Levels
               Initial Test Data
         .593
       .446
      .629
      1.905
       .600
                                                Standard:  0.41 g/mi
CM
               FORO    CHRT  MITSUB   RLL

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UJ
                   Figure 7
               Average CO Levels
               Initial Test Data
21
22
20
18
18
U
12
to
8
6
1
2
0
>
•
•
•
•
•

•

'
•




9.34

















4.31


















13.33

















23.10















8.49







                                               Standard:  9.0 g/mi
        CM     FORO    CHRT  NITSUB   ALL
                   Figure 8
              Average NOx Levels
              Initial Test Data
2.2
2.0
1.8
1.6
X
0
UJ
u
UJ
«o.e
0.8
0.4
0.2
0.0
•





-
1.52













1.81













1.38













1.96














1.63











                                               Standard:   1.5 g/mi
        CM
FORO   CMRY   NITSUB   ALL

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                                                            Table 3
                                                        Pass/pail Rates
                                                         Initial Test
MFR
GM
Ford
Chrysler
Mitsubishi
All
Number
of Vehicles
54
33
7
4
98
Total
Pass
9 (THC*)
19 (NMHC**)
4 (THC)
5(NMHC)
O(THC)
O(NMHC)
O(THC)
O(HMHC)
13(THC)
24(NMHC)
Percent
Pass
17 (THC)
35 (NMHC)
12 (THC)
15 (NMHC)
O(THC)
O(NMHC)
O(THC)
O(NMHC)
13 (THC)
24 (NMHC)
Total
Failed HC
43(THC)
30 (NMHC)
21 (THC)
17 (NMHC)
7 (THC)
6 (NMHC)
4 (THC)
4(NMHC)
75(THC)
57 (NMHC)
Percent
Failed HC
80(THC)
56 (NMHC)
64(THC)
52 (NMHC)
100 (THC)
86 (NMHC)
100 (THC)
100 (NMHC)
77(THC)
58 (NMHC)
Total
Failed CO
15
2
3
4
24
Percent
Failed CO
28
6
43
100
24
Total
Failed NOX
14
16
2
2
34
Percent
Failed NOx
26
48
29
50
1
KJ
1
35
 *Based on Total  Hydrocarbon (THC)  compared  to .41  g/mi.

**Based on Non-Methane Hydrocarbons (NMHC) compared to .41  g/mi.
  NMHC = THC x Methane Content  Correction Factor.

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                                    -13-
                                   Figure 9
                            Combined Pass/Fail Rates
                                Initial Test Data
          Fail THC,

  Fail THC, NOx
                     Fail NOx
CO
                        Fail THC
Fail THC, NMHC
                                                         Pass
                                                         Fail THC, NMHC, CO,  NOx
                                                     Fail THC, NMHC, NOx
                           Fail THC, NMHC, CO

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                                                                          Table 4
                                                               Engine Family and Manufacturer
                                                         Average tinission Levels and failure Kates
                                                                        Initial Vests
Manufacturer
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
Eftgine
Faaily
910M2KOU
920X2CBU
930H2AU
940E2CYU
940E2UI
940E4DVT
940E4DVY
910UUOJ
910Y2V
All
Hunter
of
Vehicles
6
1
8
2
12
1
1
12
11
54
MXF
.81
.81
.81
.89
.81
.81
.81
.81
.81
N/A
Average
•me
1.560
.460
.539
.785
.639
1.710
.550
.697
.490
.729
Average
twHC
1.260
.373
.436
.699
.518
1.385
.446
.564
.397
.593
Average
CD
14.80
6.23
7.60
7.36
9.91
18.13
8.65
b.63
7.68
9.34
Average
NOx
1.73
l.UO
1.12
2.04
1.90
1.79
2.22
1.10
1.47
1.52
Percent Pass
Based
on THC
0
u
13
0
50
0
0
b
9
17
Percent
Pass Based
on NtttC
O
100
25
O
50
O
O
33
55
35
Percent
Failed
THC
100
100
bb
100
42
100
100
*2
b2
80
Percent
Failed
M4HC
100
0
75
100
33
j.00
100
67
Ib
56
Percent
Failed
00
50
0
13
O
25
1UU
O
jj
27
2U
Percent
Failed
33
O
13
XU>
33
1UO
100
B i
Ib '
26
1979 California Standards:
                 HC  =  .41
                 GO  = 9.0
                 NOz = 1.5

Average Vehicle Mileage:

           43,806 miles
THC = Total HC
Failing 1HC means THC exceeded 0.41 g/mi.
t*«C = Non-Methane HC = THC x MOCF
Failing t*i*C means b*HC exceeded 0.41 g/mi.

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                 Table 4
     Engine family and Manufacturer
Average Emission Levels and Failure Rates
              Initial Tests
Manufacturer
Ford
Ford
Ford
Fbrd

Fbrd
Fbrd
Fbrd
Ford
Chrysler
Chrysler
Chrysler
Mitsubishi
Mitsubishi
Mitsubishi
All

Engine
Family
5.0AV1X150
1.6G1X128
2.3A1X150
2.3B1TF80
XR80
2.8BV1X150
3.3B1X150
4.1AX1X150
All
9CD/318/
360-4-GP
9CF-105-2-
BP
All
4G3M-C
4G3P-C
All
All

Number
of
Vehicles
7
2
12
4

2
4
2
33
3
4
7
2
2
4
98

MOCF
.79
.83
.79
.73

.79
.79
.79
N/A
.85
.85
N/A
.89
.89
N/A
N/A

Average
THC
.841
.250
.429
.480

.855
.622
.555
.569
.957
.578
.740
1.230
3.060
2.140
.733

Average
NMHC
.665
.208
.339
.350

.675
.492
.438
.446
.813
.491
.629
1.090
2.719
1.905
.600

Average
CO
3.01
1.45
3.73
4.17

13.33
6.27
2.58
4.31
20.46
7.99
13.33
20.49
25.71
23.10
8.49
Page
Average
NQx
1.42
1.91
2.22
2.10

1.36
1.32
1.52
1.81
.B6
1.78
1.38
1.12
2.80
1.96
1.63
2
Percent Pass
Based
on -JHU
0
SO
25
0

0
0
0
12
0
0
0
0
0
0
13

Percent
Pass Based
on wMHL
0
bO
25
2b

0
O
0
Ib
0
O
0
0
0
0
24

Percent
Failed
TMJ
100
O
25
75

IUO
100
100
64
100
100
100
1OO
100
100
77

Percent
Failed
tMC
100
O
17
0

100
100
100
52
100
75
86
IUO
100
100
5to

Percent
Failed
GO
O
O
U
0

50
0
O
6
*>7
25
43
IUO
100
100
44

Percer
bailee
MJK
29
bo
b7
75

O
25
50
4U
O
bu
29
O
100
bO
Jb


-------
                              -16-

family).  Based on NMHC General Motors engine family  910Y2V
 (305-CID V-8) did the best with a 55 percent pass rate  (GM
engine  family 920X2CEU had a NMHC pass rate of 100 percent but
only one vehicle was tested in that family).  No engine family
had THC based average emission levels for all three pollutants
below the standard and only GM engine families 910Y2V and
920X2CEU (one vehicle tested) had NMHC based average emission
levels  for all three pollutants below the stanoard.

      As noted above, the average HC (both THC and NMHC) levels
and failure rates are higher than the corresponding measures
for the other pollutants.  The THC and NMHC failure rates for
the individual families tend to indicate that HC failures are
occurring across all manufacturers and all families.  For
example, only three  (15 percent) of the 20 individual families
tested  had THC failure rates below 50 percent and only six
families (30 percent) had NMHC failure rates below 50 percent
for the initial tests.

      D.  Restorative Maintenance

      Following the initial tests, those vehicles that failed
to meet the 1979 California emission standards received
extensive maintenance aimed at correcting tne cause of
failure.  These vehicles were then retested.  Table 5 and
Figures 10 through 13 compare the average initial test results
with the average after maintenance test results for all of the
vehicles that received restorative maintenance and were
retested.  (Ten General Motors vehicles failed THC but passed
NMHC on the initial test.  These vehicles did not receive
maintenance and were not retested because tney met the 1979
California NMHC standard.  The data from these 10 vehicles are
not included in Table 5 or Figures 9 through 12.  Also, one
failing Ford vehicle was withdrawn from the program by the
owner before it had been repaired and retested.)  For the total
population of retested vehicles average emission level
reductions occurred for all pollutants for all manufacturers
except Ford (THC, NMHC, and CO)  and Mitsubishi  (NOx).  The
overall average emission levels for all of the retested
vehicles were reduced 0.07 g/mi (8 percent) for THC, 0.06 g/mi
(9 percent)  for NMHC, 1.43 g/mi (15 percent)  for CO, and 0.44
g/mi (24 percent) for NOx.  The overall average retest emission
levels for  all of the retested vehicles for CO and NOx were
below the applicable standards following the maintenance.
However, the average THC and NMHC retest levels failed to meet
the 0.41 g/mi standard.

      Tables 6 through 9 show the changes in emission levels
resulting from the restorative maintenance for each pollutant
separately.   Only those vehicles that failed to meet each indi-
vidual pollutant's standard on the initial test are included in
the table for that pollutant.   Presenting the data separately
for each pollutant,  rather than grouped together as in Table 5,
removes the impact of the vehicles that received maintenance
aimed at correcting  a different pollutant's emission failure

-------
                                                                         Table 5
                                                                 Averaye Rnission Levels
                                                         Initial Tests  va After Maintenance tests
                                                                for All Hetested Vehicles
Manufacturer
CM
Fbrd
Chrysler
Mitsubishi
All
Nunber of
tetested
Vehicles
35
28
7
4
74
Total Total Percent Non-
HC HC Change Methane*
Initial After Total HC Initial
Average Maintenance HC Average
.905
.605
.740
2.140
.843
.732
.660
.649
2.123
.772
19
- 9
12
1
8
.737
.475
.629
1.905
.691
Won- Hercent
Methane* HC Change CO (JU
After Non- Initial After Main-
Maintenance Methane HC Averaye tenance
.595 19
.517 - 9
.551 12
1.BB9 1
.631 9
11. bb
4.59
13.33
23.10
9.7i
b.52
5.45
11. 2b
20.74
U.2U
Hercent tUx Moot After Hercent
Change Initial Mainte- Change
CO Averaye nance MUx
26 1.77 1.30
-19 1.90 i.*7
15 l.Jb 1.19
10 1.96 2.b9
15 l.dO 1.J6
n
33
14
-47
24
1979 California Standards:
           1C  -  .41 (Non-methane)*
           CO  = 9.0
           NOK = 1.5

Average Vehicle Mileage:

           43.806 miles

•Non-nethane HC ° Ttotal HC x Methane Content Correction Factor.

-------
                       -18-
                     Figure  10
                Average  THC  Levels
            Before vs After  Maintenance
               All Retested  Vehicles
                                         BEFORE MAINTENANCE
                                         RPTER MAINTENANCE
GN     FORO    CHRT   NIT3U8
          MANUFACTURERS
                                        THC Level:  0.41 g/mi
ALL
                     Figure  11
                Average NMHC Levels
            Before vs After  Maintenance
               All Retested  Vehicles
                                         BEFORE  MAINTENANCE
                                     CD AFTER  MAINTENANCE
                                         Standard:  0.41 g/mi
       FORO    CHRT   MITSUB
          MANUFACTURERS
ALL

-------
                      -19-
                    Figure 12
               Average CO  Levels
           Before vs After Maintenance
              All Retested Vehicles
                                         BEFORE MAINTENANCE


                                     C3 AFTEA MAINTENANCE
                                          Standard:   9.0 g/mi
CM     FOAO    CHAT   NIT3UB
          MANUFACTUAEAS
ALL
                    Figure 13
               Average NOx  Levels
           Before vs After Maintenance
              All Retested Vehicles
                                         BEFORE MAINTENANCE
                                         AFTER MAINTENANCE
                                          Standard:   1.5 g/mi
CM     FOAO    CHAT   NITSUB
          MANUFACTURERS
ALL

-------
                              -20-

 from the analysis of the maintenance aimed at correcting  the
 particular pollutant of interest.  The pollutant  specific
 analysis gives a better measure of our ability to  identify ana
 correct specific causes of failure,  rfhen considered separately
 the reductions in average emission levels due to  the mainte-
 nance were 0.09 g/mi (9 percent)  for THC, 0.09 g/mi  (12 per-
 cent) for NMHC, 5.6 g/mi  (29 percent) for CO, and  1.13 g/mi
 (44 percent) for NOx.  Also, when considered separately the
 average retest emission levels for all pollutants  except NOx,
 remained above the applicable standard following  the mainte-
 nance.
                              Table 6
                      Average Total HC Levels
                      Initial Tests  vs After
              Maintenance Tests  for Retested Vehicles
             That Failed Total HC  on the Initial Test

                Number of     Total  HC     Total HC
                Retested      Initial        After        Percent
Manufacturer    Vehicles      Average     Maintenance    Reduction

GM                 33            .942        .757           20
Ford               20            .720        .783           -y
Chrysler            7            .740        .649           12
Mitsubishi          4          2.140        2.123            1
All                64            .925        .839            9
                              Table 7
                   Average Non-Methane HC Levels
                      Initial Tests  vs After
              Maintenance tests  for Retested Vehicles
          That Failed Non-Methane  HC on  the Initial Test
                 Number of   Non-Methane   Non-Methane
                 Retested    HC—Initial    HC--After     Percent
Manufacturer     Vehicles      Average     Maintenance   Reduction

GM                  30          .807          .638          21
Ford                17          .598          .619          -4
Chrysler             6          .670          .574          1*
Mitsubishi           4         1.905         1.889           1
All                 57          .807          .714          12

-------
                              -21-
                              Table 8
                         Average CO Levels
                       Initial Tests  vs After
              Maintenance tests for Retested Vehicles
                That Failed CO  on  the Initial Test
Manufacturer

GM
Ford
Chrysler
Mitsubishi
All
Number of
Retested
Vehicles

   15
    2
    3
    4
   24
  CO
Initial
Average

 18.18
 16.44
 22.26
 23.10
 19.36
          CO After
        Maintenance

           10.98
           15.99
           16.99
           20.74
           13.78
                Percent
               Reduction

                  40
                   3
                  24
                  10
                  29
                              Taole 9
                        Average NOx  Levels
                      Initial Tests  vs After
              Maintenance  tests  for Retestea Vehicles
                That Failed NOx  on the Initial Test
Manufacturer

GM
Ford
Chrysler
Mitsubishi
All
Number of
Retested
Vehicles

   14
   16
    2
    2
   34
  NOx
Initial
Average

 2.76
 2,
 2,
 2,
46
20
80
 2.59
NOx After
Maintenance

   1.42
   1.30
   1.66
   2.78
   i.46
 Percent
Reduction

   49
   47
   25
    i
   44
      The pass/fail rates for all of the retested vehicles are-
shown in Table 10 and Figures 14 through 17.   (The figures also
show total vehicles tested and initial failure rates.)  The NOx
failure rate for all manufacturers' vehicles except Mitsubishi
was significantly reduced by the maintenance.  The overall NOx
failure rate was reduced 59 percent.  General Motors' vehicles
also showed a significant decrease in tneir CO failure rate
following the maintenance.  The overall CO failure rate was
reduced 25 percent mainly as a result of the GM failure rate
decrease.  The maintenance was not effective in reducing the
THC failure rate for any of the manufacturers tested.  However,

-------
                                                       Table 10
                                        Pass/Fail Rates for Retested Vehicles*
                                        Initial versus After Maintenance Tests
                                         Numbers shown are number of vehicles
Manuf act urer
GM
Ford
Chrysler
Mitsubishi
All
Number of
Vehicles Pass
Retested Initial
35 0(THC**)
0(NMHC***)
28 O(THC)
O(NMHC)
7 O(THC)
O(NMHC)
4 O(THC)
O(tMHC)
74 O(THC)
O(NMHC)
Pass
After
Main-
tenance
4(THC)
12(tWhC)
6(THC)
7(NMHC)
O(THC)
O(NMHC)
O(THC)
O(tiMHC)
10(THC)
19(NMHC)
Failed
HC
Initial
33 (THC)
30(NMHC)
20(THCj
17(NMHC)
7(THC)
4(THC)
4(NMHC)
64 (THC)
57(CMHC;
Failed Failed Failed
HC CO NOx
After Failed After Failed After
Main- CO min- NOx Main-
tenance Initial tenance Initial tenance
31 (THC) 15 8 14 5
231NMHC)
21(THC) 2 4 10 5
NJ
7(THC) 322 1 '
4(THC) 442 3
41NMHC)
63 (THC) 24 18 34 14
52(NMHC)
  *The 10 GM vehicles that failed THC only and were not retested are not included in this table.

 **Based on Total hydrocarbons (THC) compared to .41 g/mi

***Based on non-methane hydrocarbons (NMHC) compared to .41 g/mi
   »1HC = THC x Methane Content Correction Factors.

-------
                  -23-
                Figure 14
           THC Pass/Fail Rates
                                      NOTE:
                                          TOTflL  VEHICLES
                                          FAILED  INITIAL TEST
                                          FAILED  AFTER MAINT
               The failed after main-
               tenance levels shown do
               not contain the ten GM
               vehicles that failed THC
               but were not retested.
ALL     GM     FORD    CHRY
          MANUFACTURERS
MITSUB
                Figure 15
          NMHC Pass/Fail Rates
                                     IZ3 TOTflL  VEHICLES
                                         FAILED  INITIflL  TEST
                                         FfllLED  AFTER  MfllNT
RLL     OH     FORO    CHRY   MITSUB
          MANUFACTURERS

-------
                        -24-

                      Figure 16
                 CO Pass/Fail Rates
A V V
90
80
70
«n
Ul
« 60
r
Ul
* SO
b»
O
5 10
0)
1 30
20
10
0
W
^
;/
/
/,
/
/,
y
\
'$







5«

>U
iS^
K/
\\XXX\XX\\\N
/

33
4
1^ '
v N > i \y\ •* - i i i
V XI 'y TrTsl l/bQT-i I/ J^iSd
                                     IZ3
                                         TOTAL VEHICLES
                                         FR1LEO INITIAL TEST
                                     El FAILED AFTER NAINT
ALL     GN     FORD    CHRT   MITSUB
          MANUFACTURERS
                      Figure 17
                 NOx Pass/Fail Rates
                                         TOTAL VEHICLES
                                         FAILED INITIAL TEST
                                         FAILED AFTER NAINT
ALL
        6N     FORD    CHRT   NITSUB
          MANUFACTURERS

-------
                              -25-

the General Motors NMHC failure rate was reduced by 23 percent
(seven vehicles) and as a result of this GM rate reduction the
overall NMHC failure rate was reduced 9 percent.   (The NMHC
failure rates for Ford and Chrysler increased by one.)
IV.   Failure Analysis

      Incoming vehicles received a complete inspection upon
arrival at the laboratory.  Table 11 contains a summary listing
of the problems diagnosed during the incoming inspections for
the vehicles accepted into the program.  Following this
inspection the vehicles received an initial maintenance that
was limited to the correction of maladjustments and minor
system disablements  (see Appendix 2 for a more detailed
description of the inspection and maintenance procedures and
individual vehicle maintenance).  Following the incoming
inspection and maintenance the vehicles received their initial
test.  If the vehicles failed to meet the 1979 California
standards (0.41 g/mi NMHC, 9.0 g/mi CO, and 1.5 g/mi NOx) on
the initial test they received an additional maintenance
sequence.  During this second repair sequence all of the
remaining problems diagnosed during the incoming inspection
were corrected as well as any subsequently diagnosed problems.
All repairs were intended to restore the vehicle to
manufacturer design specification.  Non-specification
adjustments (e.g., setting choke lean of manufacturer
specification) were not performed.

      Prior to the initial test, parameters such as idle
mixture, idle speed, choke setting, ignition timing, etc., were
only reset if they were outside of the manufacturers' specified
tolerances (or the EPA assigned tolerance if no tolerance
existed for a manufacturer).  Vehicles that were received with
their idle limiter caps intact were adjusted only within the
range of the limiter cap prior to the initial test.  Vehicles
that came into the program with their idle mixture limiter caps
missing or obviously tampered were assumed to be incorrectly
adjusted and were reset to the manufacturers' specifications
prior to the initial test.  These procedures were adopted so
the test vehicles would be properly adjusted for the initial
test and would approximate future vehicles with non-adjustaole
parameters.

      During the second restorative maintenance process ail
diagnosed malfunctions were repaired and all parameters were
reset to the exact manufacturers' specified settings.  Prior to
the second test the limiter caps were removed and the idle
mixture readjusted to the manufacturers' specifications when
necessary.

      In Table 11 the items that were generally corrected prior
to the initial test are marked with an asterisk (*).  To the
extent that these initial adjustments and repairs were
successful in correcting potential emission performance

-------
                                          Table 11
                                 Diagnosed Vehicle Problems
                                        All Vehicles
Problem Diagnosed
Number of Occurrences (Percent of each Manufacturer's Vehiclest
Carburetor
Fuel System
*Limiter Caps
Missing
Caps Intact
Mixture Incorrect
*Incorrect Curb
Idle Speed
* Incorrect
Fast Idle Speed
* Incorrect
Choke Adjustment
*Incorrect
Choke Pull-off
Adjustment
Defective
Choke Pull-off
Incorrect Float
Adjustment
Incorrect Carbu-
(M
6 (11)

23 (43)

24 (44)

20 (37)
5 ( 9)

11 (20)


6 (11)

4 ( 7)

0 ( 0)
Ford
25 (76)

1 ( 3)

8 (24)

0 ( 0)
2 ( 6)

1 ( 3)


2 ( b)

0(0)

5 (15)
Chrysler
6 (bb)

2 (29)

5 (71)

0 ( 0)
0 ( 0)

0 ( 0)


0 ( 0)

0 ^ 0)

0 ( 0)
Mitsubishi
4 (1OO;

0 I 0)

4 (100)

0 ( 0;
0 ( 0)

0 ( 0)


0 ( 0)

0 ( 0;

0 ( 0)
ALL
4i 1 42)

2b (27;

41 (42)

20 i 20; ,
Ivj
O\
1
7 i 7)

12 112)


B ( fa)

4 ( 4)

5 ( 5)
 retor Venturi Bypass
 Vacuum Adjustment

*—Items generally corrected prior to the initial test.

-------
Problem Diagnosed
                                  Table 11  (Continued)
                               Diagnosed Vehicle Problems
                                      All Vehicles
Number of Occurrences  (Percent of each Manufacturer *s Vehicles)
                          GM
           Ford
Chrysler
Mitsubishi
 Backpressure
 Transducer

 Plugged EGR Passage     0(0)       7  (21)      3  (43)

*—Items generally corrected prior to the initial test.

                                         Page 2
                                      1  (25)
ALL
Ignition
System
* Incorrect
Timing
* Incorrect
Spark plugs
*Fouled Spark Plugs
Defective
Vacuum Advance
EGR System
*Plugged Vacuum
Lines
Defective EGR
Valve
Incorrect EGR
Valve
Defective
19 (35) 11 (33) 1 (14) 2 (50) 33 (34)
14 (26) 1(3) 1 (14) 0(0) 16 (16)
3(6) 0(0) 2 (29) 2 (50) 7 ( 7)
0(0) 4 (12) 0(0) 2 (50) 6 ( 6)


3(6) 1(3) 0(0) 0 ( U) 4(4)

8 (15) 4 (12) 0(0) 2 (50) 14 U4)

2(4) 0(0) 0(0) 0(0) 2(2)

0(0) 2(6) 0(0) 0(0) 2(2)
                              11 (ID

-------
Problem Diagnosed
Inlet System
Defects
                                  Table 11 (Concluded)
                               Diagnosed Vehicle Problems
                                      All Vehicles
Number of Occurrences (Percent of each Manufacturer's Vehicles)
GM
Other Systems
Defective 02
Sensor
Air Injection
Defects
Evap Defects
PCV Defects
Fresh Air
1
1
5
6
4
(
(
(
2)
2)
9)
(11)
(
7)
Ford
1
2
1
3
10
( 3)
( 6)
( 3)
( 9)
(30)
Chrysler
0 I 0)
0
0
0
1
( 0)
( 0)
( 0)
(14)
Mitsubishi
0
0
0
0
0
( 0)
( 0)
( 0)
( 0)
( 0)
ALL
2
3
b
9
15
( 2)
( 3)
( 6)
( 9)
(15)
                                                                                                          I
                                                                                                          IvJ
                                                                                                          OO
                                                                                                          I
                                         Page 3

-------
                              -29-

problems, these vehicle problems did not contribute directly  to
an increase in initial test emission levels or failure rates.
However, indirect increases in emissions due to, for example,
build up of deposits in the combustion chamber, accelerated
deterioration, damage to the catalyst, etc., as a result of the
malfunction/maladjustment could not be determined.  It is
possible that these types of indirect increases could have
contributed to both initial and after maintenance emission
levels.

      As previously discussed Tables 5 through 10, ana the
related Figures 13 through 16, compare the manufacturers'
before retest performance with their after retest performance.
The CO reductions were generally the result of carburetor,
choke system, and idle mixture adjustments or repairs.   (The
idle mixture adjustments performed after the initial test
required the removal of the idle mixture limiter caps prior to
the adjustment.)   The NOx reductions were generally the result
of EGR system repairs.  Typical repairs were EGR valve replace-
ment and EGR passage cleaning.  The average NOx levels ana
failure rates were reduced more than any other pollutant.
Average THC and NMHC levels and failure rates were reduced less
than the other pollutants.  In the majority of cases the main-
tenance performed did not reduce the THC and NMHC levels
sufficiently to meet the stanaard.  The largest THC or NMHC
failure rate reduction was for GM NMHC where 7 out of 30
failing vehicles (23 percent)  met the standara based on NMHC
following maintenance.

      As pointed out above, THC and NMHC were the most often
failed pollutants and the least correctable.  The cause of
these THC and NMHC failures was not discovered curing the
program.  The potential exists for some type of catalyst
deactivation to be causing the problem (e.g., poisoning,
deterioration, carbon build-up masking adequate catalyst
performance, etc).   At present, however,  we nave no eviaence  to
support this hypothesis.  We have initiated a test program at
the Environmental Protection Agency's Motor Vehicle Emission
Laboratory in Ann Arbor, Michigan aimed at isolating the per-
formance of the catalyst from the performance of the rest of
the vehicle on some high mileage (40,000 - 50,000 miles) 1980
and 1981 model year vehicles.   This followup program shoula
allow us to determine if excess catalyst deactivation is a
major contributing factor to HC failure.

      The vehicles in some engine families experienced higher
than expected levels of malfunction for certain emission re-
lated systems.  GM engine family 940E2LU haa an EGR valve
diaphragm failure rate of 33 percent.  Four of the 12 vehicles
tested for this engine family had leaking EGR valve diaphragms.
Another GM family,  940E2CYU, had a 100 percent EGR valve failure
rate but only two vehicles were tested for this family.  Both
of these families are Buick 3.8 liter V-6 engine families.  It
is possible that these two engine families have similar enough

-------
                              -30-

 system designs  to be  treated  as  a  single  group  for  the  purpose
 of evaluating these EGR  failures but  further  investigation
 beyond the  scope of this analysis  would be  necessary  to confirm
 this.

      Ford  engine family 2.3A1X150  also experienced EGR system
 problems.   Of the 12  vehicles tested  for  this engine  family  4
 (33 percent) had plugged EGR  spacer plate passageways,  2
 (17 percent) had broken  EGR exhaust backpressure  transducers,
 and 2  (17 percent) had defective EGR  valves  (one  of the vehi-
 cles with a defective EGR valve  also  had  a plugged EGR  spacer
 plate passageway).  Another Ford engine family  (2.3B1TR80XR80)
 also had plugged EGR  spacer plate  passageways.  Two of  the four
 vehicles tested in this  family  (50 percent) suffered  from the
 plugging problem  (one of these vehicles also had  a defective
 EGR valve).  Both of  these Ford  families  are 2.3  liter  4
 cylinder engine families and, as with the GM engine families
 discussed earlier, these designs may  also be similar  enough  to
 be grouped  together.

      All of the vehicles that experienced EGR  system problems
 in the Ford and GM engine families discussed above failed to
 meet the 1.5 g/mi NOx standard on  the initial test.   The
 initial test average NOx levels  for all four of these engine
 families also failed to  meet  the 1.5  g/mi NOx standard.
 Following restorative maintenance  all but two of  the  15
 vehicles were able to meet the NOx standard and all four of  the
 engine families had after-maintenance average NOx levels at  or
 below the standard.
V.    Data Variability

      The variability of the data is important because of its
affect on the level of confidence with which we are able to
estimate in-use emission performance.  The greater the vari-
ability of the data, the wider our confidence interval for any
given sample size.  Since actual variability is fixed, we are
only able to decrease the width of the confidence interval by
increasing the sample size.  Table 12 shows the standard devia-
tion (the square root of the variance)  of the data for each
pollutant for each manufacturer, and for all manufacturers
combined for the initial tests.

      Table 12 also compares the lower 95 percent confidence
bound with the emission standard for each pollutant.  vJhere
this lower bound exceeds the standard we are 95 percent
confident that the population average or mean emission level
for that pollutant for that manufacturer exceeds the standard.
The width of the interval between the average and the lower
bound for each manufacturer is different because of differences
in each manufacturer's sample size and standard deviation.

-------
                                                Table 12
                                              Lower Bounds
                                      95 Percent Confidence Level
                                           One Sided Interval
                                              initial Tests
MFR

GM
04
Q4
GM

Ford
Ford
Ford
Ford

Chry
Chry
Chry
Chry

Mit
Mit
Mit
Mit

All
All
All
All
Lower Bound = Average - t £

Sample
Size
54
54
54
54
33
33
33
33
7
7
7
7
4
4
4
4
98
98
98
98


Pollutant
THC
NMHC
CO
NOx
THC
NMHC
CO
NOx
THC
NMHC
CO
NOx
THC
NMHC
CO
NOx
THC
NMHC
CO
NOx


t
1.674
1.674
1.674
1.674
1.694
1.694
1.694
1.694
1.943
1.943
1.943
1.943
2.353
2.353
2.353
2.353
1.661
1.661
1.661
1.661

Standard
Deviation
.517
.420
7.96
.86
.250
.198
3.82
.91
.263
.223
9.85
.73
1.524
1.357
11.39
1.07
.578
.4*8
8.14
.88
95%
Lower
Bound
.611
.497
7.53
1.32
.495
.388
3.18
1.54
.547
.465
6.1U
.84
.347
.308
9.70
.70
.636
.516
7.12
1.48
Average
Emission
Level
.729
.593
9.34
1.52
.569
.446
4.31
1.81
.740
.629
13.33
1.38
2.140
1.905
23.10
i.96
.733
.600
8.49
1.63
                                                                                        95*  Interval
                                                                                         As  Percent
                                                                                         ot  Standard

                                                                                             29
                                                                                             23
                                                                                             20
                                                                                             18
                                                                                             14
                                                                                             13
                                                                                             18

                                                                                             47
                                                                                             40
                                                                                             80
                                                                                             36

                                                                                            437
                                                                                            390
                                                                                            149
                                                                                             84

                                                                                             24
                                                                                             20
                                                                                             15
                                                                                             10
i
CM
1979 California Standards:  HC =  0.41
                           CO =  9.0
                           NOx = 1.5
THC = Total HC
NMHC = Non-methane HC = THC x MCCF
                                        (Non-methane)

-------
                              -32-

      At the 95 percent level the GM, Chrysler, and fleet-wide
 lower bounds for THC and NMHC exceed the 0.41 g/mi standard.
 The Ford lower bound for THC exceeds the 0.41 g/mi standard
 while the Ford NMHC lower bound was below the 0.41 g/mi
 standard.  Mitsubishi's lower bound for CO exceeds the 9.0 g/mi
 standard.  Ford's lower bound exceeds the NOx standard.

      Also shown in Table 12 is the one-sided 95 percent
 interval as a percent of the applicable standard.  This value
 is the amount, as a percentage, by which each manufacturer's
 test vehicle sample average must exceed the standard for each
 pollutant before we can be 95 percent confident that the
 standard has been exceeded by that manufacturer's vehicles.  As
 discussed above these values are based on each manufacturer's
 data variability as measured by the standard deviation and the
 manufacturer's sample size.  The size of the interval increases
 as the standard deviation increases and the interval decreases
 as the sample size increases.  If, for example, we compare the
 Ford THC interval (18 percent) with the Mitsubishi THC interval
 (437 percent) we can see how sample size and standard deviation
 affect the interval.  Ford had the best average THC performance
 of the manufacturers tested and Mitsubishi had the worst.
 However, due to Ford's small standard deviation and larger
 sample size we can predict THC noncompliance for Ford but we
 are unable to do so for Mitsubishi.  We are unable to predict
 noncompliance (at the 95 percent level) for Mitsubishi due to
 its large interval.   This large interval is the result of
 Mitsubishi's large standard deviation ana small sample size.

      For the manufacturers in this test program for which a
 relatively large sample was tested (GM and Ford) the percent of
 sample intervals range from a high of 29 percent (GM THC) to a
 low of 13 percent (GM NOx and Ford CO).  The relatively small
 sample sizes for Mitsubishi and Chrysler make it difficult to
 predict emission performance based the test data.

      We can also quantify the confidence level for our
 estimated standard deviation in a manner similar to what we
 have done for the emission levels above.  The confidence
 interval for standard deviation is also a function of sample
 size.   For our fleet sample size of 98 vehicles the 95 percent
confidence interval for the standard deviation estimate is plus
or minus 14 percent.  This means that the standard deviation
 that we have calculated for the test fleet from our sample will
be within plus or minus 14 percent of the true standard
deviation of the population 95 percent of the time.
VI.   Discussion

      Before developing conclusions based on the testing
conducted under this program, a general discussion of the data
and its limitations is in order.  First of all, the vehicle
sample was relatively small.  As indicated earlier in this
report, this data gathering effort is only the first and
smallest phase of the overall project.  Because the test sample

-------
                              -33-

is small and the actual in-use vehicle population is large and
diverse, differences may exist between the characteristics of
the sample and those of the actual population.  Also, the
vehicles tested were all certified for sale in California.  AS
discussed earlier, 1979 model year California vehicles were
selected because they represented the most current emission
control technology for vehicles with sufficient mileage at the
time testing took place.  Because only California vehicles were
tested in this program care must be exercised in using these
data to predict emission performance of vehicles in other
vehicle populations.  A further limitation of the vehicle
sample is its technological mix.  The sample vehicles consisted
primarily of oxidation catalyst-equipped vehicles.  The data
generated by these oxidation catalyst vehicles may not give a
good indication of how future vehicles equipped with three-way
closed loop systems will perform.

      While some limitations do exist in the data due to sample
construction constraints, the following trends in the data are
apparent:

      A.  Based on the data generated in this program it
appears that vehicles in the 40,000 to 50,000-mile range are on
average not meeting the .41 g/mi HC standard.  For the vehicles
in this program the overall and individual manufacturer average
THC and NMHC emission levels were above the 0.41 g/mi standard.
Also, the failure rates were high (greater than 50 percent) for
all manufacturers tested.

      3.  Typical restorative maintenance procedures (fuel
metering and ignition system repairs) were unable to
significantly reduce the HC failure rate.  Neither the AESi
mechanics nor the manufacturers' representatives (when present)
were successful in diagnosing and repairing the HC failures.
After repairs the overall and individual manufacturer average
THC and NMHC levels remained above the 0.41 g/mi standard for
the retested vehicles.

      C.  The overall average CO emission level was below the
9.0 g/mi standard.  Individually, Chrysler and Mitsubishi had
problems with CO.  H-owever, CO levels appeared to respond
favorably to restorative maintenance.  CO emission levels and
failure rates were both reduced following maintenance.  CO
failures were typically the result of carburetor and choke
system problems which were relatively easy to diagnose and
repair.

      D.  The overall average NOx emission level was slightly
(9 percent)  above the 1.5 g/mi standard.  Individually Ford and
Mitsubishi had difficulty with NOx.  The NOx levels and failure
rates responded very well to restorative maintenance.  The NOx
level and failure rate were both reduced by the maintenance.
NOx failures were typically the result of EGR system problems.
These were easily diagnosable and repairable due in part to
their similarity to NOx problems discovered at low mileage in
previous in-use compliance programs.

-------
                              -34-

      These data trends tend to indicate that HC compliance may
be a significant problem.  As discussed in the introduction
section of this report, we assumed at the outset that because
manufacturers are currently responsible for emission compliance
through 50,000 miles we would ngt encounter a significant
amount of noncompliance in our test program.  The CO and NOx
emission performance of the test vehicles is the type of
performance that was anticipated; average levels at or very
near the standard and some engine families and/or manufacturers
performing better than others.  However, the HC standard was
exceeded on average by all manufacturers,  in addition, the
vast majority of engine families also had average HC levels
above the standard.  This indicates that the HC problem is a
general rather than a design, engine family, or manufacturer
specific problem.  If this limited sample HC noncompliance is
indicative of the total current vehicle population, the causes
of this noncompliance must be found before implementation of
any compliance program that tests in-use vehicles in the 40,000
to 50,000-mile range.  Assuming that this problem can be
remedied by design change, such a new compliance program could
be viewed as more stringent than the current compliance program
although the stringency of the standards as provided by the
Clean Air Act is not changed.

      The current compliance program has the flexibility to
test vehicles in the 40,000 to 50,000-mile range and if the HC
noncompliance trend persists as further data are collected,
some type of current compliance program response may be
required.  At the present time, however, the cause of the HC
problem has not been determined, and may not be manifested in
the newer 3-way catalyst technology.  As discussed earlier, we
have initiated a test program aimed at isolating engine
performance from catalyst performance to determine to what
extent each of these subsystems contribute to the problem.
Until such time as the extent and cause of the HC problem are
accurately defined, the correct remedial compliance response
will be difficult to formulate.

      In addition to measuring emission levels of vehicles
between 40,000 to 50,000 miles in this test program, we also
wanted to quantify the variability of emission data from
vehicles in this mileage range.  From the information gathered
on the variability of the data we will be able to assess our
ability to accurately determine average emission levels.  AS
indicated earlier, the percent of standard 95 percent lower
confidence bound for the larger samples (GM and Ford) were in
the 10 percent to 30 percent range.  For the small samples
taken in this program these seem acceptable.

-------
                              -35-

VII.  Conclusions

      This study was undertaken to develop information
pertaining to the emission performance of properly used and
maintained vehicles in the 40,000 to 50,000-mile range and to
use this information to evaluate the feasibility of incorpor-
ating this type of testing into an emission compliance pro-
gram.  This report has presented the data and discussed the
relationship of the data to the issues of program stringency
and possible noncompliance remedies.  Based on the data
generated during this program we have developed the following
conclusions:

      A.  Although the current compliance program requires
emission compliance through 50,000 miles, the data from the
vehicles tested in this program indicate that there may be a
general in-use HC noncompliance problem.  All manufacturers
tested had average THC and NMHC levels above the .41 g/mi
standard and HC failure rates in excess of 50 percent.  The
true extent and cause of the HC noncompliance problem was not
determined during this test program.  Therefore, we were unable
to determine what type remedial action is appropriate for cor-
recting the apparent HC noncompliance problem.  Further testing
and failure analysis is necessary.

      B.  CO and NOx performance was such that, for these
pollutants, program changes incorporating testing in the 40,000
to 50,000-mile range do not appear to present nonconformance
problems or require the development of alternative remedial
mechanisms.  The average CO and NOx levels were at or near the
standards and traditional restorative maintenance procedures
appeared to be effective.  We must point out, however, that our
evaluation of CO and NOx performance was conducted on vehicles
designed to meet the 1979 California standards of 9.0 g/mi CO
and 1.5 g/mi NOx and that the resulting conclusions may not be
applicable to current Federal vehicles designed to meet the
3.4 g/mi CO and 1.0 g/mi NOx Federal standards.

      C.  For the data collected in this test program the data
variability was such that average emission levels could be
determined within acceptable confidence ranges when samples of
sufficient size were taken.

      These conclusions are restricted by the data limitations
as outlined in the Discussion section above,  it is important
to consider that the data sample was small (98 vehicles) and
from a restricted population (California vehicles) .  Given the
limitations of the data, the projection of the trends observed
in this test program to other vehicle populations may not be
totally appropriate.  However, the trends observed, particu-
larly the trend for HC noncompliance, tend to indicate the need

-------
                              -36-

for further evaluation of vehicles near the end of their
statutory useful life (50,000 miles).  AS indicated earlier in
this report, additional data on 1980 and 1981 model year
Federal vehicles is presently being collected.  As the
investigation continues and additional data become available
our ability to quantify both emission levels and emission
variability will improve.

-------
APPENDICES

-------
APPENDIX 1
Test Vehicle Sample
Manufacturer
GM
GM
GM
GM
GM
GM
GM
GM
GM
Ford
Ford
Ford
Ford
Ford
Ford
Ford
Chrysler
Chrysler
Mitsubishi
Mitsubishi
Total
Engine
Family
910L4RIJ
910Y2V
910W2KQU
920X2CEU
930H2AU
940E2CYU
940E2LU
940E4DVT
940E4DVY
1.6G1X128
2.3A1X150
2.3BlTR80xR80
2.8BVlxl50
3.381x150
4.1A1X150
5.0AVlxl50
9CD-318/360-4-GP
9CF-105-2-BP
4G3M-C
4G3P-C

Description
CID - # Cyl
305 - V8
305 - V8
98 - L4
151 - LA
260 - V8
231 - V6
231 - V6
231 - V6
231 - V6
98 - L4
140 - LA
140 - LA
171 - V6
200 - L6
250 - L6
302 - V8
318 - V8
105 - LA
98 - LA
98 - LA

Number
Of Vehicles
12
11
b
1
8
2
12
1
1
2
12
4
2
4
2
7
3
4
2
_2
9b

-------
                                                       Appendix  2
                                            Individual Vehicle  Test Results
1979  MODEL YEAR CALIFORNIA  VEHICLE TEST RESULTS

 MFC   ENG                VEH TEST   INER     HP
MILE
              HC
                           CO
                                                                                              Page  1
                                      NOX
                                                 MPG
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM.
•GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
91OL4RU
9IOL4RU
9IOL4RU
9IOL4RU
91OL4RU
91OL4RU
9IOL4RU
91OL4RU
91OL4RU
91OL4RU
9IOL4RU
9IOL4RU
91OL4RU
91OL4RU
91OL4RU
9IOL4RU
91OL4RU
91OL4RU
91OL4RU
91OL4RU
91OV2KOU
91OW2KOU
91OW2KQU
91OW2KQU
91OW2KOU
9IOW2KQU
91OW2KQU
91OW2KOU
9 1OW2KQU
91OV2KOU
91OW2KOU
9 1OW2KOU
91OV2V
9IOV2V
91OV2V
91OV2V
91OV2V
91OV2V
91OV2V
91OV2V
91OV2V
91OY2V
91OV2V
91OV2V
91OV2V
91OV2V
91OV2V
91OY2V
92OX2CEU
93OH2AU
93OH2AU
930H2AU
93OH2AU
93OH2AU
415
415
419
421
422
422
426
435
435
442
442
456
458
45B
5O3
503
536
536
537
537
427
427
432
432
443
443
447
447
513
513
515
515
433
434
437
437
444
445
445
448
514
514
518
527
527
533
534
534
428
436
436
439
439
44O
SPEC
RM
SPEC
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
35OO
35OO
35OO
35OO
35OO
350O
35OO
3500
35OO
4OOO
4OOO
4OOO
35OO
35OO
35OO
3SOO
4OOO
4OOO
35OO
35OO
250O
25OO
22SO
225O
25OO
250O
25OO
25OO
25OO
2500
225O
225O
4000
4000
4000
40OO
40OO
4OOO
4OOO
4OOO
4OOO
4OOO
4OOO
4OOO
4OOO
40OO
40OO
4OOO
30OO
35OO
35OO
3500
350O
3500
12 O
12 O
12.4
12.2
12. 0
12. O
124
12.4
12 4
12.5
12.5
12.8
12. 0
12. 0
11.3
113
12.8
12.8
11.3
113
9.2
92
92
9.2
92
9 2
9.2
9.2
9.2
92
9.2
92
13 3
1O 2
97
9 7
97
1 1 .6
It .6
13 3
1O. 2
10.2
10 2
10.2
1O 2
116
1O. 2
1O. 2
10.4
12.2
12 2
12.2
12.2
12.2
49262
49283
412O4
45876
42627
42668
4OI61
40018
4OO39
42O16
42O36
41641
44998
45O40
42333
42353
4O1O2
4OI24
4692O
46939
42374
42394
42045
42O86
49115
49136
49391
49453
44581
446O3
47765
47787
42331
412O9
42242
42264
45O74
4O933
4O95O
46215
40965
4O987
45151
47752
47775
49199
46768
46789
41O34
41711
41737
4O8I8
4O843
46826
.54
48
.36
.48
.52
.52
.46
.66
.66
1 .01
.72
.51
1 38
.37
.53
.61
.69
.47
1 .22
.65
1 .62
1 .35
1 .42
1 .31
2.20
2. 19
1 .70
1 85
.57
.52
1 .82
2.41
.42
.46
.45
.43
.47
.35
.35
.48
55
.44
.42
.97
.69
.40
.42
.56
.46
.57
.45
.55
.56
.62
5
9
4
7
14
6
5
6
6
4
3
2
18
5
4
6
1 1
6
16
4
19
1O
a
6
35
26
1 1
1 1
6
5
7
16
2
4
8
7
7
6
7
4
9
8
8
16
to
4'
9
13
6
6
3
7
7
. a
77
.03
46
55
. 10
88
98
.08
.49
.as
66
89
87
.50
.69
3O
85
26
42
26
63
92
. 13
36
O2
33
82
OO
95
.88
26
12
41
88
59
6O
71
73
43
6O
55
41
98
68
04
81
49
79
23
28
74
88
54
13
1 .32
1 O3
86
1 O3
1 18
1 . 13
1 .OO
1 12
1 2O
1 74
1 52
1 12
89
1 .05
1 07
1 29
99
1 00
83
1 34
3 90
1 79
1 26
1 54
1 O9
1 .23
1 22
1 42
1 . 13
1 23
1 77
1 61
.99
1 O3
2.93
1 53
1 28
3 5J
1 . 1O
96
1 IB
1 24
1 13
94
1 .23
1 . 12
111
1 .09
1 OO
1 24
1 . 15
1 63
1 4O
121
15.77
15.38
15 68
15 77
15. 06
.15.26
15. 19
16.34
J6.O9
14 .85
14 87
13 57
14 62
15.96
15 54
16 13
14 OO
14.3O
14 45
16 53
24 .28
24 22
23 4O
23 73
21 .83
22 OS
25 66
24 . 35
23.57
23 33
23.89
22 91
13.42
12 88
15. 17
14 4O
14 36
15 56
1421
13 59
14.41
14 OO
13 35
14 OS
13 94
14 14
13.73
14 .07
19.63
16.99
17. OB
16.95
16.96
16. 17

-------
                                                      Appendix 2
                                            Individual Vehicle Test Results
1979 MODEL YEAR CALIFORNIA VEHICLE TEST  RESULTS
 MFG  ENG.
                        VEH TEST
                                   INER
                                            HP
                                                   MILE
                                                                 HC
                                                                             CO
                                                                                              Page  2
                                                                                        NOX
                                                                                                    MPG
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
GM
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
93OH2AU
93OH2AU
93OH2AU
93OH2AU
93OH2AU
93OH2AU
93OH2AU
93OH2AU
93OH2AU
94OE2CYU
94OE2CYU
94OE2CYU
94OE2CYU
94OE2LU
94OE2LU
94OE2LU
940E2LU
94OE2LU
94OE2LU
94OE2LU
94OE2LU
94OE2LU
94OE2LU
940E2LU
94OE2LU
94OE2LU
940E2LU
94OE2LU
94OE2LU
94OE2LU
94OE2LU
94OE2LU
94OE4DVT
94OE4DVT
94OE4DVV
94OE4DVV
I .6G1X128
t .6GIXI28
1 .6GIXI28
2.3AIX15O
2 . 3A1X15O
2 3A IX ISO
2. 3A IX ISO
2. 3A IX ISO
2 3A IX ISO
2 3A IX ISO
2 3AIXI5O
2 . 3A1X15O
2. 3A IX ISO
2. 3A IX ISO
2 3AIXI5O
2 3A IX ISO
2. 3A IX ISO
2 . 3A1XI5O
440
4SO
455
455
502
5O2
526
538
538
4 2O
420
516
516
423
423
424
424
424
425
425
429
43O
431
431
438
44 t
441
449
449
528
53O
531
5O9
5O9
5IO
SIO
416
416
504
4O3
405
405
407
407
408
4O8
412
412
5O7
517
517
S2O
S2O
521
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
ADD1
SPEC
RM
SPEC
SPEC
SPEC
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
SPEC
SPEC
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
SPEC
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
SPEC
RM
SPEC
RM
SPEC
35OO
350O
35OO
35OO
35OO
350O
350O
35OO
3SOO
3500
35OO
3500
35OO
35OO
35OO
35OO
3500
350O
35OO
3500
35OO
350O
35OO
35OO
350O
35OO
35OO
35OO
350O
350O
35OO
35OO
350O
35OO
35OO
35OO
2OOO
20OO
2OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3OOO
3000
12.2
12 .2
12 2
122
12.2
12 2
12.2
12.2
12 2
12.2
12 2
12.2
12 2
12. 0
12 .O
113
113
11.3
12.5
12.5
12.2
12.2
12 5
12.5
9. 1
12.5
12.5
9. 1
9. 1
113
113
11.3
12.2
12 2
12.2
122
7.3
7.3
7.3
9.2
9.2
92
9. 1
9. 1
1O. 2
1O 2
to 5
10.5
1 1 .O
9. 1
9. 1
9. 1
9. 1
9.2
46847
45O96
4O837
4O859
44844
44866
4OS79
4O659
4O682
42766
42787
4O424
4O444
42651
42672
42633
42653
42718
43981
44O01
41386
43771
46624
46646
49350
42514
42534
412O3
41225
45O8S
4799O
45613
4O542
4OS64
44528
44556
46195
46218
417O9
41277
41293
41315
4155O
41572
46963
470O3
451O1
45123
4454O
40725
4O747
43418
43439
45511
.47
.45
.61
.53
.54
.52
.39
.58
.58
.52
.44
1 05
.54
.84
.33
2.61
1 . 19
.65
95
.71
.37
. 19
.46
.46
.29
.27
28
.64
58
.33
.41
.31
1.71
77
.55
.63
.22
.25
.28
.33
.35
.38
1.07
1.07
.37
.33
.34
.37
.34
.43
.53
.60
.69
.39
6
a
9
8
a
6
5
7
5
7
7
7
6
17
3
49
32
12
15
1O
6
2
5
6
3
3
3
2
2
4
4
4
18
6
8
8
1
1
1
2
2
2
6
7
2
4
2
3
I
12
14
5
5
2
41
27
41
94
15
19
65
06
7O
22
12
SO
61
O8
47
45
13
24
18
81
4O
59
67
14
62
SO
.68
.72
93
O2
48
16
, 13
OO
.65
53
.50
64
4O
87
.07
.66
.36
.32
15
15
81
97
79
05
69
. 18
44
71
1 24
1 00
97
1 OO
95
t 34
95
1 05
1 2O
•>. 6O
1 28
3 O8
1 67
1 32
111
3 38
1 OO
1 25
4 O3
1 35
91
1 .35
2.47
72
111
3 54
1 O8
1 38
1 .43
1 .31
99
1 O3
1 .79
1 .64
2 22
2 24
2 32
2 65
1 50
9O
3 47
1 52
4 .73
92
3 84
92
3 00
1 O6
1 54
.51
52
2.33
84
1 . 75
16 55
16 . 23
16 . 14
IS 77
15.48
1711
15.42
16.73
16 82
19.51
19.36
17 3O
17 66
17. 35
17 67
16 43
17 33
17 .48
17 O1
16.69
16 76
17 52
17.91
15.48
16 86
17 . 78
17.02
15.86
16.07
17 49
18 62
17.55
18. O2
17 3O
17. 12
16 83
25 46
25 19
24 .91
16 67
19.59
19 65
18.85
18 9O
18.85
IB 21
20 55
19.98
19 39
17 .45
17 13
19.61
19.61
19.81

-------
                                                      Appendix 2
                                            Individual Vehicle Test Results
1979 MODEL YEAR CALIFORNIA VEHICLE  TEST RESULTS

 MFC  ENG.               VEH TESI    INER      HP
                                                  MILE
                                                                MC
                                                                            CO
                                                                                        MOX
                                                                                             Page  3
                                                                                                   MPG
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
FORD
CHRV
CHRY
CHRV
CHRV
CHRV
CHRV
CHRV
CHHV
CHRV
CHRV
CHRV
2 3A IX ISO
2 3A1XI5O
2 3A IX 150
2.3A 1X15O
2. 3A IX ISO
2.3A1X ISO
2.3B1TR8OXRBO
2 3B1TR8OXRBO
2 3BITR8OXR8O
2.3B1TR8OXR8O
2 3B1TR8OXR8O
2.3B1TR8OXR8O
2 3BITR8OXR8O
2 . 8BV1X ISO
2 . 8BV1X ISO
2.8BV1X ISO
2.8BV1X15O
3. 3B1X ISO
3 3B IX ISO
3. 3B IX ISO
3 3B IX ISO
3. 38 IX ISO
3. 38 IX ISO
3. 3B IX ISO
3. 3B IX ISO
4. 1AIXI5O
4 . 1 A IX ISO
4. IAIX15O
4. IAIX15O
S.OAV1X ISO
S.OAVIXISO
S.OAVIXISO
5.OAV1X ISO
S.OAVIX ISO
5.OAVIX ISO
S.OAVIXISO
S.OAVIX ISO
S.OAVIXISO
5.OAVIXISO
S.OAVIXISO
S.OAVIX ISO
S.OAVIXISO
S.OAVIX ISO
9CD-3I8/36O-4-GP
9CD-318/360-4-GP
9CD-31B/36O-4-GP
9CD-318/36O-4-GP
9CD-3I8/36O-4-GP
9CO-318/36O-4-GP
9CF-IO5-2-BP
9CF- 1O5-2-BP
9CF-IO5-2-BP
9CF- 1O5-2-BP
9CF-IO5-2-BP
S2I PM
522 SPEC
525 SPEC
525 RM
529 SPEC
529 RM
413 SPEC
414 SPEC
414 RM
417 SPEC
417 RM
535 SPEC
535 RM
402 SPEC
402 RM
505 SPEC
SOS RM
4OI SPEC
4O1 RM
4O6 SPEC
4O6 RM
512 SPEC
512 RM
519 SPEC
519 RM
4O4 SPEC
4O4 RM
511 SPEC
511 RM
4O9 SPEC
4O9 RM
4 1O SPEC
4 1O RM
411 SPEC
411 RM
418 SPEC
418 RM
501 SPEC
SOI RM
506 SPEC
5O6 RM
524 SPEC
524 RM
453 SPEC
453 RM
454 SPEC
454 RM
459 SPEC
459 RM
452 SPEC
452 RM
46O SPEC
460 RM
523 SPEC
3OOO 9
3OOO 9
3OOO 9
3OOO 9
3OOO 9
30OO 9
3OOO 9
3OOO 9
3OOO 9
3OOO 9
3OOO 9 -
3OOO 9 '
3OOO 9 '
3OOO 1O.
3OOO 1O.
3OOO 1O
3OOO 1O
35OO 12.
35OO 1 2 .
3OOO 1 1 (
3OOO 1 1 (
3OOO 1 1 . (
3OOO 1 1 (
35OO 12.
35OO 12.
3500 10.
35OO 1O
35OO 1 1
35OO 1 1
3500 10
350O 1O
35OO 12
3500 12
35OO 1O
35OO IO
4OOO 1 1
4OOO 1 1
350O 11.?
35OO 1 1 . £
35OO IO
3500 IO
35OO 1O.C
35OO 1O.C
4OOO 1 1 .«
400O 11 t
4OOO 14
4OOO 14 . 1
4OOO lit
4OOO 114
275O 72
2750 72
25OO 8 2
25OO 8 2
25OO 7.6
1 45533
1 47541
2 45717
2 45739
2 4 1995
2 42O4O
J 47449
» 45187
< 452O7
1 41 181
7 41202
1 4O465
1 4O4R6
41737
41765
41018
4 IO4O
47O74
47O92
; 4514O
i 45161
> 43039
; 43O6I
433O9
43334
4O988
4 IOO9
42O8O
42 tOO
48148
48168
487O9
48727
4335O
43371
4O381
4O41O
42365
42386
43469
4349O
> 42884
) 429O5
1 4547O
1 45491
4288O
429OO
44199
44221
41O19
41O4O
43956
43978
42171
44
.40
.27
.33
.26
32
48
.53
49
56
131
35
39
63
63
t O8
93
69
74
6O
65
57
63
.63
57
.55
.58
56
.48
1 O3
.77
1 IO
1 .62
68
BO
.87
82
72
.91
79
.82
70
.62
.67
.68
1 .20
.63
1 00
1 . IO
.45
.49
SB
56
66
2
2
2
4
2
3
5
3
3
5
13
2
3
5
5
20
17
8
8
5
5
8
G
3
2
1
2
3
2
1
4
5
9
3
5
2
2
2
4
1
1
4
3
8
8
21
9
31
32
5
4
6
a
13
4 I
38
04
47
29
59
3O
72
84
O/
01
SB
•IP
83
?7
83
?0
29
67
O6
38
13
7 1
59
95
49
03
66
87
71
53
65
81
87
23
07
52
O1
2fi
O5
26
69
15
21
45
75
97
42
17
05 2
20 1
86 1
O9
62 1
1 O4
1 07
1 7B
85
1 75
61
1 53
> 70
1 61
1 91
1 54
1. 20
1 34
1 1G
"> or,
1 15
1 28
B5
83
? 37
39
19
64
86
O8
31
18
73
9O
28
98
4O
4O
27
32
.83
34
62
27
27
16
27
39
Ol
00
05
31
52
54
83
99
50
87
19
19.58
20. 23
2O B5
IB . 7f,
1891
17 23
2O 5O
2 1 45
21 15
19 26
19 56
22 O8
2113
17 52
18 IK
16.5.1
16 4C)
13 98
13 39
1791
17 34
21 19
2 1 97
15 56
16 17
16 7O
15 S3
17 55
17.29
16 39
15.47
15 OO
1461
15 65
15 92
15 4O
15 13
15 16
1 4 98
16 49
16 3O
16 6O
16 64
15 29
15 55
14 46
14 63
14 O5
14 O9
24 48
24 94
22 77
22 28
24 O3

-------
                                                      Appendix  2
                                           Individual Vehicle  Test Results
1979 MODEL YEAR CALIFORNIA VEHICLE TEST RESULTS

 MFG  ENG.               VEH TEST   INEH      HP
MILE
              HC
                                     NOX
                                                                                             Page  4
                                                MPG
CHRV
CHRV
CHRV
MITS
MITS
MITS
MITS
MITS
MITS
MITS
MITS
9CF- 1O5-2-BP
9CF- 1O5-2-BP
9CF- 1O5-2-BP
4G3M-C
4G3M-C
4G3M-C
4G3M-C
4G3P-C
4G3P-C
4G3P-C
4G3P-C
523
532
532
446
446
SOS
508
451
451
457
457
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
SPEC
RM
25OO
2500
25OO
225O
225O
225O
225O
25OO
250O
225O
2250
7
8
a
B
8
a
8
a
8
8
8
6
. 4
4
7
7
8
8
. 7
7
7
7
422OO
42274
42296
42516
42572
48852
48872
4766O
47683
4672O
46742



1
1
1
I
4
3
1
1
49
62
.59
27
53
18
66
4O
.80
.71
50
R
6
7
17
16
23
26
38
27
12
12
B3

-------
                          Appendix  3

             Test Vehicle procurement, Inspection,
        Maintenance Procedures, and Maintenance summary
      A.  Vehicle Procurement

          The vehicle procurement process used in this test
program was similar to the procurement processes used to pro-
cure test vehicles from the public in the QMS' emission factors
and recall programs.  An owner registration list was purchased
and randomized.  Certified letters were mailed to all indivi-
duals on the list.  This initial mailing was followed up by a
second, first class mailing and a telephone contact.  When an
individual responded favorably to one of these contacts they
were asked a series of questions to evaluate the acceptability
of their vehicle.  If the responses to the questions indicated
that the vehicle was acceptable it was brought to the labora-
tory for inspection and testing.  A vehicle was considered
acceptable for this program if the vehicle met the following
criteria (minor deviations were permitted where, in the opinion
of EPA engineers, no significant emission level difference
would result):

          1.  Was still owned by the original purchaser.

          2.  Had accumulated between 40,000 and 50,000 miles.

          3.  Had not been operated in an atypical manner
(taxi, racing, overheated, etc.).

          4.  Had not been operated using leaded fuel if
unleaded fuel was required.

          5.  Had not received accident damage to the engine or
emission control systems.

          6.  Had not been altered by the installation of
non-OEM equipment (exhaust headers, ignition system,
aftermarket air-conditioning, etc.).

          7.  Had received proper scheduled maintenance in
accordance with the manufacturers' recommendations.

          8.  Had not received unscheduled maintenance repairs
to the engine, drivetrain, or emission control system by other
than an appropriate dealer.

          9.  Had not had any alterations or modifications made
to any emission control system components.

          Vehicles that met these criteria were accepted into
the program.

-------
                              -2-

      B.  Vehicle Inspection and Maintenance

          Vehicles that were determined to be acceptable for
the program by the procurement screening process were brought
to the AESI facility for inspection and testing.  Each vehicle
was inspected and test driven prior to testing.  Vehicles were
rejected from the program during the inspection/test drive if
they:

          1.  Had in excess of 0.05g/gal of lead in their fuel,
or failed the plumbtesmo tailpipe patch test.

          2.  Had an obvious engine, transmission, or braking
problem requiring major/expensive repair.

          3.  Had a major emission control system disablement
(e.g., system removed).

          Also during the vehicle inspection the operational
status of the vehicle and its emission control systems were
determined.  Prior to the initial test each vehicle received a
complete mechanical inspection and limited maintenance
consisting of the following operations if necessary:

          1.  Adjust the idle mixture if the adjustment plugs
have been removed or obviously tampered,  if equipped with
limiter caps, adjust within the range of control.

          2.  Set the idle RPM, ignition timing, dwell, and
choke rod adjustment if outside of the EPA specified tolerance
range (e.g., + 2° ignition timing, +_ 100 idle rpm).

          3.  Replace the spark plugs and secondary wiring as
required to obtain the proper firing voltage.

          4.  Repair exhaust system leaks.

          5.  Reroute misrouted vacuum lines.

          6.  Replace non-OEM equivalent spark plugs.

          7.  unplug blocked vacuum lines.

          8.  Replace non-OEM PCV valves and/or EGR valves.

          The actual maintenance performed prior to the initial
test on each vehicle is shown in the attachment to this
Appendix.  Following the initial inspection and maintenance
sequence each vehicle was tested for emissions,  if the vehicle
failed to meet the 1979 California emission standards the
vehicle was given a second much more extensive repair sequence
consisting of the following operations if necessary:

          1.  Change the oil and filter.

          2.  Change the spark plugs.

-------
                               -3-

          3.  Set the  ignition timing, dwell,  idle  rpm,  and
choke rod adjustment to specification.

          4.  Set the  idle mixture to specification.  Utilize
the manufacturer's artificial  enrichment  (propane gain)
procedure if specified.

          5.  Repair any emission control system malfunctions.

          6.  Service  the carburetor, choke and hoses.

          7.  Check and correct the Early Fuel Evaporation
System.

          8.  Check and correct the carburetor bolt torque.

          9.  Check and correct the vacuum advance and hoses.

          10. Replace  the fuel filter.

          11. Replace  the PCV  valve and service the hoses.

          12. Replace  the oxygen sensor.

          13. Check and correct the idle stop solenoid.

          14. Replace  the air  cleaner element.

          15. Check and correct the carburetor vacuum break.

          16. Check and correct the Evaporative Control  system
and replace the filter.

          17. Check and correct the fuel line.

          18. Check and correct the engine valve clearance.

          19. Repair all emission control system malfunctions
except those requiring carburetor replacement, internal  engine
component replacement,  or catalyst replacement.  (Some vehicles
had their carburetors  replaced at the manufacturer's request.
However carburetors were not replaced routinely.)

      The restorative maintenance performed on each vehicle
following the initial  test is  also shown in tne attachment to
this Appendix.   The restorative maintenance performed after the
initial test was somewhat different than the maintenance per-
formed before the initial test in that many routine procedures
were performed (see the restorative maintenance list of  proce-
dures) .   Also as part of the restorative maintenance tune-up
all engine parameters were reset to the exact manufacturer's
specifications.   These adjustments were made as necessary on
all vehicles and are not shown individually in the attachment
because those parameters that were outside of the specification
tolerance range were reset prior to the initial test leaving

-------
                              -4-

only minor adjustments to be made for these parameters during
the restorative maintenance tune-up procedure.  These types of
items are simply indicated in the attachment as a tune-up.  Any
significant non-routine maintenance operations that were per-
formed during restorative maintenance are shown individually in
the attachment to the Appendix.  Following the second mainte-
nance sequence the vehicles were retested.

-------
Manufacturer

General Motors

General Motors
Engine
Family

910L4RU

910L4RU
General Motors     910L4RU

General Motors     910L4RU

General Motors     910L4RU



General Motors     910L4RU


General Motors     910L4RU


General Motors     910L4RU


General Motors     910L4RU



General Motors     910L4RU

General Motors     910L4RU



General Motors     910L4RU




General Motors     910L4RU


General Motors     910L4RU
        ATTACHMENT

        Appendix 3

1979 Model Year California
     AESI  Test Vehicle
        Maintenance

                     Maintenance Performed
 yen      Test         Prior to Testing

 415     initial     Adjust idle speed

 415     Res Mnt     Tune-up
                     Remove idle mixture plugs and
                     adjust idle mixture
                     Replace fuel tank vent hose at
                     canister

 419     initial     Adjust idle speed

 421     Initial     Adjust idle speed

 422     Initial     Adjust choke
                     Adjust idle mixture
                     Replace spark plugs

 422     Res Mnt     Tune-up
                     Adjust carburetor float level

 426     Initial     Adjust idle speed
                     Replace NO. 4 spark plug

 435     Initial     Adjust ignition timing
                     Adjust choke pull-off

 435     Res Mnt     Tune-up
                     Remove idle mixture plugs
                     and adjust idle mixture

 442     initial     Adjust idle speed

 442     Res Mnt     Tune-up
                     Remove idle mixture plugs and adjust
                     idle mixture

 456     Initial     Adjust ignition timing
                     Adjust fast idle speed
                     Adjust idle speed
                     Replace spark plugs

 458     initial     Adjust fast idle speed
                     Unplug EGR vacuum line

 458     Res Mnt     Tune-up
                     Replace choke pull-off
                     Remove idle mixture plugs and adjust
                     idle mixture

-------
                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

General Motors

General Motors



General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors

General Motors



General Motors
Engine                           Maintenance Performed
Family       veh      Test         Prior to Testing

910L4RU      503     Initial     Adjust choke pull-off

910L4RIJ      503     Res Mnt     Tune up
                                 Remove idle mixture plugs and adjust
                                 idle mixture

910L4RU      536     Initial     Adjust idle speed
                                 Adjust fast idle speed
                                 Adjust choke pull-off
                                 Adjust air pump belt
                                 Replace fuel filter

910L4RU      536     Res Mnt     Tune-up
                                 Remove idle mixture plugs
                                 and adjust idle mixture
                                 Repair fresh air duct

910L4RU      537     Initial     Adjust idle speed
                                 Adjust fast idle speed
                                 Adjust choke

910L4RU      537     Res Mnt     Tune-up
                                 Adjust carburetor float level
                                 Remove idle mixture plugs and adjust
                                 idle mixture
                                 Replace fresh air duct

910W2KQU     427     Initial     Adjust idle speed
                                 Adjust fast idle speed
                                 Replace spark plugs

910W2KQU     427     Res Mnt     Tune-up
                                 Replace choke pull-off diaphram
                                 Remove idle mixture plugs and adjust
                                 idle mixture

910W2KQU     432     Initial     Replace spark plugs

910W2KQU     432     Res Mnt     Tune-up
                                 Remove idle mixture plugs
                                 and adjust idle mixture

910W2KQU     443     Initial     Adjust idle speed
                                 Replace spark plugs
                                 Reconnect crankcase vent tube
                                         Page 2

-------
                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

General Motors
General Motors
General Motors

General Motors


General Motors



General Motors



General Motors


General Motors

General Motors


General Motors
General Motors
Engine
Family
910W2RQU
910W2KQU
910W2KQU
910W2KQU
910W2KQU
910W2KQU
910W2KQU
91GY2V
910Y2V
Veh
443
447
447
513
513
515
515
433
434
Test
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Initial
910Y2V
910Y2V
437
Initial
437     Res Mnt
Maintenance Performed
  Prior to Testing

Tune-up
Adjust carburetor float level
Remove idle adjustment plugs and
adjust idle mixture

Adjust idle mixture
Adjust idle speed
Replace spark plugs
Unplug EGR vacuum line

Tune-up

Replace spark plugs
Adjust ignition timing

Tune-up
Remove idle mixture plugs and
adjust idle mixture

Adjust ignition timing
Adjust idle speed
Adjust fast idle speed

Tune-up
Replace carburetor

Adjust choke

Adjust choke pull-off
Adjust fast idle speed

Adjust ignition timing
Adjust fast idle speed
Unplug EGR vacuum line
Repair PCV vent filter
Replace carburetor air horn
gasket

Tune-up
Replace EGR valve
Adjust choke
                                         Page 3

-------
1979 Model Year California
     AESI  Test Vehicle
       Maintenance
Manufacturer
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
General Motors
Engine
Family
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
910Y2V
920X2CEU
930H2AU
Veh
444
445
445
448
514
514
518
527
527
533
534
534
428
436
Test
Initial
Initial
Res Mnt
Initial
Initial
Res Mnt
Initial
Initial
Res Mnt
Initial
Initial
Res Mnt
Initial
Initial
Maintenance Performed
Prior to Testing
Adjust idle mixture
Adjust idle speed
Repair TAG heat tube
None
Tune-up
Replace EGR valve
Replace PCV hose
Adjust ignition timing
Replace spark plugs
Adjust ignition timing
Adjust fast idle speed
Tune-up
Remove idle mixture plugs and
adjust idle mixture
Adjust ignition timing
Adjust fast idle speed
Repair choke linkage
Adjust choke
Tune-up
Adjust carburetor float level
Remove idle mixture plugs and
adjust idle mixture
Replace No. 3 spark plug
Adjust choke pull-off
Tune-up
Replace vacuum hose for PCV
and canister purge
Adjust idle speed
Adjust ignition timing
                     Replace spark plugs
          Page 4

-------
                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

General Motors



General Motors

General Motors



General Motors


General Motors
General Motors
Engine
Family

930H2AU



930H2AU

930H2AU



930H2AU


930H2AU
General Motors     930H2AU

General Motors     930H2AU
930H2AU
General Motors     930H2AU

General Motors     930H2AU



General Motors     930H2AU



General Motors     930H2AU


General Motors     930H2AU
                    Maintenance Performed
Veh      Test         Prior to Testing

436     Res Mnt     Tune-up
                    Remove idle mixture plugs and adjust
                    idle mixture

439     Initial     Adjust ignition timing

439     Res Mnt     Tune-up
                    Remove idle mixture plugs and
                    adjust idle mixture

440     Initial     Adjust idle speed
                    Replace spark plugs

440     Res Mnt     Tune-up
                    Remove idle mixture plugs and
                    adjust idle mixture

450     Initial     Adjust idle speed

455     Initial     Adjust idle speed
                    Adjust fast iale speed

455     Res Mnt     Tune-up
                    Remove idle mixture plugs ana
                    adjust iale mixture

502     Initial     Adjust fast idle speed

502     Res Mnt     Tune-up
                    Remove idle mixture plugs and adjust
                    idle mixture

526     Initial     Adjust ignition timing
                    Replace spark plugs
                    Adjust fast idle speed

538     Initial     Repair fuel leak at the
                    carburetor

538     Res Mnt     Tune-up
                    Remove idle mixture plugs
                    and adjust idle mixture
                                         Page 5

-------
                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

General Motors

General Motors



General Motors

General Motors
General Motors
General Motors

General Motors



General Motors
General Motors

General Motors
General Motors
Engine
Family
940E2CYU
940E2CYU
940E2CYU
940E2CYU
940E2LU
940E2LU
940E2LU
940E2LU
940E2LU
940E2LU
Veh
420
420
516
516
423
423
424
424
424
425
Test
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Extra T(
Initial
940E2LU
425
Res Mnt
Maintenance Performed
  Prior to Testing

Adjust carburetor

Tune-up
Replace EGR valve
Replace canister purge hose

Adjust fast idle

Tune-up
Replace EGR valve
Replace choke pull-off
Replace 02 sensor

Adjust ignition timing
Replace spark plugs
Adjust idle speed
Adjust fast idle speed

Tune-up

Adjust ignition timing
Adjust secondary choke pull-off
Adjust fast idle speed

Tune-up
Replace EGR valve
Replace canister
Replace carburetor

Accumulate 50 miles

Adjust ignition timing
Adjust fast idle speed
Replace PCV vent valve
Adjust choke pull-off
Repair carburetor vent
hose at canister

Tune-up
Replace EGR valve
Replace secondary choke pull-off
Remove idle mixture plugs ana aajust
idle mixture
                                         Page 6

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                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer
General Motors
General Motors
General Motors
General Motors
General Motors

General Motors

General Motors
General Motors


General Motors



General Motors

General Motors

General Motors
Engine
Family

940E2LU
940E2LU
940E2LU
940E2LU
940E2LU

940E2LU

940E2LU
940E2LU



940E2LU




940E2LU

940E2LU

940E2LU
Veh      Test

429     Initial



430     Initial
431     Initial
431     Res Mnt
438     Initial

441     Initial

441     Res Mnt
449     Initial


449     Res Mnt



528     Initial

530     Initial

531     Initial
Maintenance Performed
  Prior to Testing

Adjust secondary choke pull-off
Adjust fast idle speed
Replace spark plugs

Adjust ignition timing
Adjust secondary choke pull-oft
Reconnect air pump delay valve
vacuum line

Adjust ignition timing
Adjust idle speed
Adjust primary choke pull-off
Reconnect PCV vent filter to
air cleaner

Tane-up
Remove idle mixture plugs
and adjust idle mixture
Replace EGR valve

Replace TAG air heat hose

Replace No. 6 spark plug wire

Tune-up
Replace EGR valve
Remove idle mixture plugs ana adjust
idle mixture

Adjust idle speed
Install air horn gasket

Tune-up
Remove idle mixture plugs and
adjust idle mixture

Adjust ignition timing

Adjust fast idle speed

Adjust ignition timing
Replace secondary choke pull-off
Adjust idle speed
Adjust fast idle speed
                                         Page 7

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                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

General Motors
General Motors
General Motors
General Motors
Ford



Ford


Ford



Ford
Ford

Ford



Ford
Engine
Family

940E40VT
940E4DVT
940E4DVY
940E4DVY
1.6G1X128



1.6G1X128


1.6G1X128



2.3A1X150
2.3A1X150

2.3A1X150



2.3A1X150
Veh

509
509
510
510
416



416


504



403
405

405



407
 Test

Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Initial
Initial

Res Mnt



Initial


 Page 8
Maintenance Performed
  Prior to Testing

Adjust idle speed
Adjust idle mixture
Replace spark plugs
Replace incorrect EGR valve

Tune-up
Replace turbo wastegate
actuator

Adjust ignition timing
Adjust idle speed
Replace incorrect EGR valve
Replace No. 2 spark plug wire

Tune-up
Replace choke pull-off
Replace power enrichment
vacuum regulator

Adjust ignition timing
Adjust idle mixture
Repair fuel leak

Tune-up
Clean EGR passage

Adjust idle mixture
Adjust idle speed
Connect TAG sensor vacuum hose

Adjust ignition timing
Adjust idle mixture
Replace PCV vent hose and
connector on air cleaner

Repair distributor cap

Tune-up
Replace EGR valve
Clean plugged EGR passage

Adjust ignition timing
Connect vacuum advance hose

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                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

Ford


Ford

Ford


Ford

Ford



Ford



Ford

Ford


Ford


Ford
Ford


Ford



Ford

Ford


Ford
Engine
Famil
             Veh      Test

2.3A1X150    407     Res Mnt


2.3A1X150    408     Initial

2.3A1X150    408     Res Mnt


2.3A1X150    412     Initial
   \
2.3A1X150    412     Res Mnt



2.3A1X150    507     Initial



2.3A1X150    517     Initial

2.3A1X150    517     Res Mnt


2.3A1X150    520     Initial


2.3A1X150    520     Res Mnt
2.3A1X150    521     Initial


2.3A1X150    521     Res Mnt



2.3A1X150    522     Initial

2.3A1X150    525     Initial


2.3A1X150    525     Res Mnt
Maintenance Performed
  Prior to Testing

Tune-up
Clean plugged EGR passage

None

Tune-up
Clean plugged EGR passage

Adjust idle mixture

Tune-up
Replace EGR backpressure
transducer

Adjust idle mixture
Adjust idle speed
Adjust choke

Adjust idle mixture

Tune-up
Replace air duct

Replace vacuum line to TAC unit
Replace vacuum line to choke pull-off

Tune-up
Replace bGR valve
Replace air duct
Replace PCV vent hose connector

Adjust ignition timing
Adjust idle mixture

Tune-up
Replace air duct
Replace PCV vent valve

Adjust idle mixture

Adjust ignition timing
Adjust idle mixture

Tune-up
Replace air duct
Clean plugged EGR passage
                                         Page 9

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                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

Ford


Ford


Ford


Ford

Ford
Ford

Ford


Ford



Ford
Ford



Ford



Ford

Ford
   Engine
   Family       Veh

   2.3A1X150    529


   2.3A1X150    529


2.3B1TR80XR80   413


2.3B1TR80XR80   414

2.3B1TR80XR80   414
2.3B1TR80XR80   417

2.3B1TR80XR80   417


2.3B1TR80XR80   535



2.3B1TR80XR80   535
   2.8BV1X150   402
   2.8BV1X150   402
   2.8BV1X150

   2.8BV1X150
505

505
         Test

        Initial


        Res Mnt


        Initial


        Initial

        Res Mnt
        Initial

        Res Mnt


        Initial



        Res Mnt
Initial



Res Mnt



Initial

Res Mnt

 Page 10
Maintenance Performed
  Prior to Testing

Adjust idle mixture
Adjust choke pull-off

Tune-up
Replace EGR backpressure transducer

Adjust idle mixture
Replace gas cap

None

Tune-up
Clean plugged EGR passage
Replace EGR valve
Replace 02 sensor

Adjust idle speed

Tune-up
Clean rust from plugged TVS

Adjust ignition timing
Adjust idle speed
Adjust idle mixture

Tune-up
Replace canister purge
control vacuum line
Clean plugged EGR passage

Adjust ignition timing
Adjust idle speed
Tighten fuel line

Tune-up
Tighten fuel line
Repair carburetor linkage

Adjust venturi control vacuum

Tune-up

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                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer
Pord
Ford
Ford
Pord
Ford
Ford
Ford
Ford
Ford
Ford
Ford
Ford
Ford
Engine
Family
3.3B1X150
3.3B1X150
3.3B1X150
3.3B1X150
3.3B1X150
3.3B1X150
3.3B1X150
3.3B1X150
4.1A1X150
4.1A1X150
4.1A1X150
4.1A1X150
5.0AV1X150
Veh
401
401
406
406
512
512
519
519
404
404
511
511
409
Test
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Maintenance Performed
Prior to Testing
None
Tune-up
Replace choke pull -off
Repair fuel line
Replace carburetor fresh air inlet
hose
Adjust idle mixture
Adjust idle speed
Replace EGR vacuum line
Tune-up
Replace EGR and vacuum advance TVS
Replace EGR valve
Adjust idle speed
Adjust idle mixture
Tune-up
Adjust idle mixture
Tune-up
None
Tune-up
Adjust ignition timing
Adjust idle mixture
Adjust spark plug gaps
Tune-up
Adjust carburetor venturi oypass
Ford
5.0AV1X150   409
Res Mnt
                                         Page 11
vacuum
Adjust idle speed
Free stuck fast idle cam
Repair vacuum leak

Tune-up
Replace distributor vacuum advance

-------
                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

Ford
Ford


Ford



Ford



Ford


Ford


Ford


Ford


Ford



Ford

Ford
Engine
Family
5.0AV1X150
5.0AV1X150
5.QAV1X150
5.QAV1X150
5.0AV1X150
5.0AV1X150
5.0AV1X150
5.0AV1X150
5.0AV1X150
5.0AV1X150
5.QAV1X150
Veh
410
410
411
411
418
418
501
501
506
506
524
Test
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Pord
5.0AV1X150   524
Res Mnt
Maintenance Performed
  Prior to Testing

Adjust ignition timing
Tighten air pump belt
Adjust carburetor venturi bypass
vacuum

Tune-up
Replace distributor vacuum advance

Adjust carburetor venturi bypass
vacuum
Free stuck fast idle cam

Tune-up
Replace air duct vacuum motor
Replace heated air duct

Adjust idle mixture
Adjust ignition timing

Tune-up
Replace distributor vacuum advance

Adjust carburetor venturi bypass
vacuum

Tune-up
Replace distributor vacuum advance

Replace TAG heat tube
Adjust carburetor venturi bypass
vacuum

Tune-up

Adjust ignition timing
Reconnect air bypass valve vacuum
hose
Adjust choke
Replace spark plugs
Adjust idle mixture

Tune-up
Replace TAG vacuum motor
                                         Page 12

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1979 Model Year California
    AESI  Test  Vehicle
       Maintenance
Manufacturer
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Chrysler
Engine
Family
9CD-318/
360-4-GP
9CD-318/
360-4-GP
9CD-318/
360-4-GP
9CD/318
360-4-GP
9CD/318
360-4-GP
9CD/318
360-4-GP
9CF-105-
2-BP
9CF-105-
2-BP
9CF-105-
2-BP
9CF-105-
2-BP
9CF-105-
2-BP
9CF-105-
2-BP
9CF-105-
2-BP
9CF-105-
2-BP
Veh
453
453
454
454
459
459
452
452
460
460
523
523
532
532
Test
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Initial
Res Mnt
Maintenance Performed
Prior to Testing
Adjust idle mixture
Tune-up
Adjust idle mixture
Adjust idle speed
Replace spark plugs
Repair fuel line
Tune-up
Adjust ignition timing
Adjust idle mixture
Adjust idle speed
Replace spark plugs
Tune-up
Adjust idle mixture
Adjust idle speed
Reconnect vacuum source for TAC,
choke pull-off, and spark
control transducer
Tune-up
Clean plugged EGR passage
Replace carburetor mounting spacer
Adjust idle mixture
Adjust idle speed
Tune-up
Clean plugged EGR passage
Adjust idle mixture
Adjust idle speed
Tune-up
Adjust idle speed
Adjust idle mixture
Tune-up
Clean plugged EGR passage
         Page 13

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                               1979 Model Year California
                                    AESI Test Vehicle
                                       Maintenance
Manufacturer

Mitsubishi


Mitsubishi



Mitsubishi


Mitsubishi
Mitsubishi
Mitsubishi
Mitsubishi
Mitsubishi
Engine
Family

4G3M-C


4G3M-C



4G3M-C


4G3M-C
4G3P-C
4G3P-C
4G3P-C
4G3P-C
Veh

446


446



508


508
451
451
457
457
 Test

Initial


Res Mnt



Initial


Res Mnt
Initial
Res Mnt
Initial
Res Mnt

 Page 14
Maintenance Performed
  Prior to Testing

Adjust idle speed
Adjust idle mixture

Tune-up
Replace distributor vacuum advance
unit

Adjust idle speed
Adjust idle mixture

Tune-up
Repair stuck sub EGR valve
Replace distributor vacuum advance
unit

Adjust idle speed
Adjust idle mixture
Adjust ignition timing
Replace spark plugs

Tune-up
Clean EGR passage
Repair stuck sub EGR valve

Adjust distributor dwell
Adjust ignition timing
Secure distributor cap
Regap No. 3 spark plug
Adjust idle speed
Adjust idle mixture

Tune-up

-------