EPA-AA-IMS/80-11
Data Summary Tables On The
Effects Of Specific Maintenance Types
On The Emissions From
In-Use Light Duty Vehicles
Failing Idle Test Outpoints
December, 1980
Notice
Technical Reports do not necessarily represent final EPA decisions or posi-
tions. They are intended to present technical analysis of issues using data
which are currently available. 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.
David Brzezinski
Inspection/Maintenance Staff
Emission Control Technology Division
Office of Mobile Source Air Pollution Control
Office of Air, Noise, and Radiation
U.S. Environmental Protection Agency
-------
The Tables in this report were compiled from data selected from the computer
data records from several testing programs. Except in the Portland Study NOx
Analysis Tables, only vehicles which received at least one repair and retest
sequence were selected from the testing programs for summary in this report.
No effort was made to create a sample which would contain a specific mix of
model years or vehicle types. Caution should be used in extrapolating any
measured changes from this report to real world changes which might be
observed in an in-use fleet.
Vehicles which did not receive all test sequences in programs with more than
one repair and retest step have had their emission levels from their previous
test sequence carried forward to any missing test sequence. This reflects the
fact that the repair in the missing sequence was not judged as necessary in
the testing program and therefore the previous test sequence would represent
the properly "repaired" emission levels of that vehicle for the missing test
sequence. This assumption affects Tables 1 through 6.
The "as-received" column in Tables 1 through 18 represent the emissions and
rates for only those vehicles which received at least one repair and retest
sequence in the testing program. This may not reflect the overall emission
levels and rates for the test program sample as a whole.
-------
INDEX
Table
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Program
Restorative Maintenance
Restorative Maintenance
FY77 Emission Factor
FY77 Emission Factor
FY77 Emission Factor
FY77 Emission Factor
Portland Element II
Portland Element II
Portland Element II
Portland Element II
Portland Element III
Portland Element III
Portland Element II
Portland Element II
Portland Element II
Portland Element II
Portland Element III
Portland Element III
Model
Years
1975-76
1975-76
1975-79
1975-79
1975-80
1975-80
1972-74
1972-74
1975-77
1975-77
1975-77
1975-77
1972-74
1972-74
1975-77
1975-77
1975-77
1975-77
Idle Cutpoints
IHC(PPM)/IC(%)
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
225/1.0
300/3.0
Repairs
Three Step Restorative Maintenance
Three Step Restorative Maintenance
Carburetor Idle Mixture Adjustment
Carburetor Idle Mixture Adjustment
Three Step Restorative Maintenance
Three Step Restorative Maintenance
Carburetor Repairs
Carburetor Repairs
Carburetor Repairs
Carburetor Repairs
Carburetor Repairs
Carburetor Repairs
Typical I/M Maintenance
Typical I/M Maintenance
Typical I/M Maintenance
Typical I/M Maintenance
Typical I/M Maintenance
Typical I/M Maintenance
Portland Study - FTP and HFET NOx Measurements
19
20
21
22
23
Effect of Typical I/M Repairs
Comparison of NOx Measurements
Comparison of NOx Measurements
Comparison of NOx Measurements
Significance of Changes in NOx
on NOx Measurements
on 1972-74 Vehicles
on 1975-77 Vehicles
on 1975-77 Vehicles
in Portland.
in Eugene and
in Eugene and
in Eugene and
Portland Element II at Quarterly Intervals.
Portland Element II at Quarterly Intervals.
Portland Element III at Quarterly Intervals.
Measurements Between Quarterly Tests in Oregon.
-------
Table 1.
Restorative Maintenance Sample
(195 1975-1976 Model Year Vehicles)
Average Mileage:
8070 Miles
Idle
Idle
HC Cutpoint:
CO Cutpoint:
(Idle Scores Measured
As
(195
Idle Test:
Average Idle HC (PPM)
Average Idle CO (Z)
IHC Pass Rate (Z)
ICO Pass Rate (Z)
Idle Test Pass Rate (X)
Federal Test Procedure:
Average FTP HC (GM/MI)
Average FTP CO (GM/MI)
Average FTP NO (GM/MI)
FTP HC Pass Rate (%)
FTP CO Pass Rate (Z)
FTP NO Pass Rate (Z)
FTP Test Pass Rate (Z)
Highway Fuel Economy Test:
Average HFET HC (GM/MI)
Average HFET CO (GM/MI)
Average HFET NO (GM/MI)
Clayton Key Mode:
High Cruise HC (PPM)
High Cruise CO «)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (Z)
Low Cruise NO (PPM)
Received
Vehicles)5
158.1
1.86
75.9
52.8
51.3
1.64
28.0
3.11
56.9
41.0
56.9
11.3
.37
4.75
3.55
37.7
.114
1346
42.6
.126
897
225 PPM
1.0 Z
in Neutral
or Park Gear)
Vehicles Which
Test As Received
RECV
281.1
3.70
50.5
3.2
0.0
2.32
46.3
2.75
26.3
7.4
72.6
2.1
.47
7.68
3.34
42.7
.182
1335
50.1
.186
927
AFT2_1
255.6
3.21
57.9
15.8
9.5
2.13
41.1
2.49
35.8
12.6
85.3
9.5
.44
6.81
3.04
39.5
.164
1211
46.5
.150
814
Fail Idle
(95 Vehicles)*
AFT32
82.7
.28
93.7
90.5
87.4
1.09
11.7
2.61
84.2
82.1
88.4
66.3
.27
3.72
3.05
34.6
.144
1234
37.2
.048
845
AFT43
76.9
.30
94.7
91.6
88.4
1.02
10.7
2.46
89.5
87.4
92.6
75.8
.25
3.18
2.89
32.8
.131
1145
36.4
.071
764
1: After correction of any disablements and maladjustments other than idle
air/fuel mixture and idle speed.*
2: After adjustment of idle speed and idle air/fuel mixture.*
3: After replacement of any defective components and a major tune-up.*
4: Some vehicles do not complete all test sequences. The emission values for
these vehicles are carried forward from the previously completed test sequence.
5: The total Restorative Maintenance program included 300 1975-1976 vehicles.
These 195 vehicles are those which have received at least one additional test
sequence besides the as-received tests.
All repairs performed by laboratory mechanics.
-------
Table 2.
Restorative Maintenance Sample
(195 1975-1976 Model Year Vehicles)
Average Mileage:
8070 Miles
Idle HC Outpoint: 300 PPM
Idle CO Outpoint: 3.0 %
(Idle Scores Measured in Neutral or Park Gear)
As Received
(195 Vehicles)5
Idle Test:
Average Idle HC (PPM) 158.1
Average Idle CO (Z) 1.86
IHC Pass Rate (Z) 81.5
ICO Pass Rate (Z) 70.8
Idle Test Pass Rate (Z) 67.2
Vehicles Which Fail Idle
Test As Received (64 Vehicles)4
RECV
362.9
4.60
28.1
3.1
0.0
AFT21
322.2
3.86
40.6
17.2
9.4
AFT32
97.0
.33
92.
87.
84.4
AFT43
94.0
.35
92.2
90.6
85.9
Federal Test Procedure:
Average FTP HC (GM/MI) 1.64
Average FTP CO (GM/MI) 28.0
Average FTP NO (GM/MI) 3.11
FTP HC Pass Rate «) 56.9
FTP CO Pass Rate (Z) 41.0
FTP NO Pass Rate (Z) 56.9
FTP Test Pass Rate (%) U.3
2.62
52.6
2.75
12.5
4.7
78.1
1.6
2.32
45.2
2.40
25.0
12.5
93.8
10.9
1.12
12.5
2.59
79.
79.
92.
65.6
1.06
11.1
2.41
85.9
85.9
95.3
75.0
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .37
Average HFET CO (GM/MI) 4.75
Average HFET NO (GM/MI) 3.55
.53
8.91
3.37
.48
7.73
2.97
.28
4.50
3.06
.26
3.66
2.83
Clayton Key Mode:
High Cruise HC (PPM) 37.7 51.7 46.2 38.6 37.3
High Cruise CO (%) .114 .240 .213 .187 .165
High Cruise NO (PPM) 1346 1516 1333 1386 1265
Low Cruise HC (PPM) 42.6 60.9 55.0 40.9 41.6
Low Cruise CO (Z) .126 .248 .196 .050 .079
Low Cruise NO (PPM) 897 1037 872 937 841
1: After correction of maladjustments and disablements other than idle
air/fuel mixture and idle speed.*
2: After adjustment of idle speed and idle air/fuel mixture.*
3: After replacement of any defective components and a major tune-up.*
4: Some vehicles do not complete all test sequences. The emission values for
these vehicles are carried forward from the previously completed test sequence.
5: The total Restorative Maintenance program included 300 1975-1976 vehicles.
These 195 vehicles are those which have received at least one additional test
sequence besides the as-received tests.
* All repairs performed by laboratory mechanics.
-------
Table 3.
Emission Factor FY77 Sample
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (Z)
Federal Test Procedure;
Average FTP HC (GM/MI)
Average FTP CO (GM/MI)
Average FTP NO (GM/MI)
FTP HC Pass Rate (Z)
FTP CO Pass Rate (Z)
FTP NO Pass Rate (Z)
FTP Test Pass Rate (Z)
Highway Fuel Economy Test
Average HFET HC (GM/MI)
Average HFET CO (GM/MI)
Average HFET NO (GM/MI)
Federal 3-Mode Test:
High Cruise HC (PPM)
High Cruise CO (Z)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (Z)
Low Cruise NO (PPM)
(71 1975-1979 Model
Average Mileage:
Idle HC Cutpoint
Idle CO Cutpoint
As Received
(71 Vehicles)*
397.3
3.55
39.4
32.4
23.9
2.44
37.8
2.06
25.4
12.7
70.4
1.4
.71
9.54
2.55
(20 Vehicles)3
100.5
.409
720
98.7
.507
824
Year Vehicles)
25003 Miles
: 225 PPM
: 1.0 Z
Vehicles Which Fail
Idle Test As Received (54 Vehicles)
As After
Received Maintenance^
499.7 241.5
4.59 .42
20.4 68.5
11.1 87.0
0.0 59.3
2.75 1.43
42.2 14.6
2.10 2.10
13.0 70.4
9.3 72.2
70.4 75.9
0.0 40.7
.73 .51
8.76 6.48
2.54 2.29
(10 Vehicles)3
95.4 74.1
.244 .456
867 730
87.4 116.9
.352 .410
865 788
1: Those vehicles in the FY77 Emission Factor Program which were tested after only
carburetor air/fuel mixture related repairs.*
2: Adjustment of the carburetor air/fuel mixture and related adjustment (timing,
idle speed).*
3: Only some of the vehicles selected for this analysis also received the loaded
mode testing.
* All repairs performed by laboratory mechanics.
-------
Table 4.
Emission Factor FY77 Sample
(71 1975-1979 Model Year Vehicles)
Average Mileage: 25003 Miles
Idle HC Outpoint: 300 PPM
Xdle CO Outpoint: 3.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(71 Vehicles)1
397.3
3.55
50,
49,
Vehicles Which Fail
Idle Test As Received (44 Vehicles)
As After
Received Maintenance^
572.8
5.30
20,
18,
38.0
0.0
242.6
.38
81.8
100.0
81.8
Federal Test Procedure:
Average FTP HC (GM/MI) 2.44
Average FTP CO (GM/MI) 37.8
Average FTP NO (GM/MI) 2.06
FTP HC Pass Rate (%) 25.4
FTP CO Pass Rate (%) 12.7
FTP NO Pass Rate (%) 70.4
FTP Test Pass Rate (%) 1.4
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .71
Average HFET CO (GM/MI) 9.54
Average HFET NO (GM/MI) 2.55
2.98
47.6
1.91
6.8
6.8
75.0
0.0
.74
9.41
2.20
1.42
15.2
1.94
72.7
68.2
79.5
45.5
.48
6.88
1.97
Federal 3-Mode Test:
High Cruise HC (PPM)
High Cruise CO «)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (%)
Low Cruise NO (PPM)
(20 Vehicles)3
100.5
.409
720
98.7
.507
824
(9 Vehicles)3
100.6
.231
867
85.3
.380
814
77.0
.462
724
118.1
.442
758
1: Those vehicles in the FY77 Emission Factor Program which were tested after only
carburetor air/fuel mixture related repairs.*
2: Adjustment of the carburetor air/fuel mixture and related adjustment (timing,
idle speed).*
3: Only some of the vehicles selected for this analysis also received the loaded
mode testing.
* All repairs performed by laboratory mechanics.
-------
Table 5.
Emission Factor FY79 Sample
(91 1975-1980 Model Year Vehicles)
Average Mileage:
Idle HC Outpoint:
Idle CO Outpoint:
As Received
(91 Vehicles)5
20020 Miles
Idle Test:
Average Idle HC (PPM) 189.7
Average Idle CO (2) 2.02
IHC Pass Rate (%) 73.6
ICO Pass Rate (%) 56.0
Idle Test Pass Rate (%) 52.7
Federal Test Procedure:
Average FTP HC (GM/MI) 1.75
Average FTP CO (GM/MI) 27.6
Average FTP NO (GM/MI) 2.21
FTP HC Pass Rate (%) 47.3
FTP CO Pass Rate (%) 31.9
FTP NO Pass Rate (%) 58.2
FTP Test Pass Rate U) 0.0
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .42
Average HFET CO (GM/MI) 6.41
Average HFET NO (GM/MI) 2.67
Federal 3-Mode:
High Cruise HC (PPM)
High Cruise CO U)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (2)
Low Cruise NO (PPM)
(30 Vehicles)6
40.1
.112
950
56.7
.385
681
225 PPM
1.0 %
Vehicles Which Fail Idle
Test As Received (43 Vehicles)4
RECV
350.5
4.13
44.2
7.0
0.0
2.10
33.7
2.05
14.0
20.9
67.4
0.0
.50
6.41
2.49
52.2
.121
874
73.5
.463
667
AFT21
319.0
3.61
48.8
16.3
9.3
1.93
28.4
1.96
39.5
30.2
69.8
7.0
.45
5.23
2.45
/in
\ 19
44.5
.077
704
63.8
.422
504
AFT32
159.6
.64
88.4
88.4
79.1
1.27
13.7
2.04
74.4
60.5
69.8
39.5
.35
3.78
2.43
Vehicles)6—
27.5
.071
716
35.9
.235
511
AFT43
119.8
.58
86.0
86.0
76.7
1.17
13.2
2.03
74.4
67.4
72.1
44.2
.34
3.79
2.41
28.3
.071
739
35.7
.221
508
1: After correction of any disablements and maladjustments other than idle
air/fuel mixture and idle speed.*
2: After adjustment of idle speed and idle air/fuel mixture.*
3: After replacement of any defective components and a major tune-up.*
4: Some vehicles do not complete all test sequences. The emission values for
these vehicles are carried forward from the previously completed test sequence.
5: Only those vehicles in the FY79 Emission Factor Program which received at least
one of the subsequent repair sequences were chosen for this analysis.
6: Only some of the vehicles selected for this analysis also received the
loaded-mode testing.
* All repairs performed by laboratory mechanics.
-------
Table 6.
Emission Factor FY79 Sample
(91 1975-1980 Model Year Vehicles)
Average Mileage:
Idle HC Outpoint:
Idle CO Outpoint:
As Received
(91 Vehicles)5
20020 Miles
Idle Test:
Average Idle HC (PPM) 189.7
Average Idle CO (%) 2.02
IHC Pass Rate (%) 78.0
ICO Pass Rate (%) 74.7
Idle Test Pass Rate (%) 69.2
Federal Test Procedure:
Average FTP HC (GM/MI) 1.75
Average FTP CO (GM/MI) 27.6
Average FTP NO (GM/MI) 2.21
FTP HC Pass Rate (Z) 47.3
FTP CO Pass Rate (%) 31.9
FTP NO Pass Rate U) 58.2
FTP Test Pass Rate (%) 0.0
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .42
Average HFET CO (GM/MI) 6.41
Average HFET NO (GM/MI) 2.67
Federal 3-Mode:
High Cruise HC (PPM)
High Cruise CO (%)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (%)
Low Cruise NO (PPM)
(30 Vehicles)6
40.1
.112
950
56.7
.385
681
300 PPM
3.0 %
Vehicles Which Fail
Idle
Test As Received (28 Vehicles)4
RECV
465.9
5.41
28.6
17.9
0.0
2.33
36.2
1.90
35.7
28.6
78.6
0.0
.46
4.45
2.29
61.6
.068
813
79.3
.273
674
AFT2*
426.5
4.75
46.4
32.1
14.3
2.09
28.7
1.96
39.3
35.7
71.4
3.6
.39
3.25
2.47
-(12 Vehi(
54.9
.058
774
62.0
.188
576
AFT32
209.3
.92
89.3
85.7
78.6
1.34
13.0
2.06
75.0
64.3
71.4
42.9
.29
1.82
2.43
33.8
.058
784
38.4
.140
584
AFT43
145.0
.82
85.7
89.3
78.6
1.18
12.6
2.04
75.0
75.0
71.4
50.0
.30
2.14
2.39
33.8
.055
816
35.9
.111
598
1: After correction of any disablements and maladjustments other than idle
air/fuel mixture and idle speed.*
2: After adjustment of idle speed and idle air/fuel mixture.*
3: After replacement of any defective components and a major tune-up.*
4: Some vehicles do not complete all test sequences. The emission values for
these vehicles are carried forward from the previously completed test sequence.
5: Only those vehicles in the FY79 Emission Factor Program which received at least
one of the subsequent repair sequences were chosen for this analysis.
6: Only some of the vehicles selected for this analysis also received the
loaded-mode testing.
* All repairs performed by laboratory mechanics.
-------
Table 7.
Portland Element II Sample
(16 1972-1974 Model Year Vehicles
Which Received Only Carburetor Maintenance)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
50970 Miles
225 PPM
1.0 %
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(16 Vehicles)
465.9
5.01
37.5
6.3
0,0
Vehicles Which Fail
Idle Test As Received (16 Vehicles)
As After Carb.
Received Maintenance*
465.9
5.01
37.5
6.3
0.0
260.9
1.06
62.
62.
43.8
Federal Test Procedure:
Average FTP HC (GM/MI) 3.53
Average FTP CO (GM/MI) 61.7
Average FTP NO (GM/MI) 2.87
FTP HC Pass Rate (%) 50.0
FTP CO Pass Rate (%) 6.3
FTP NO Pass Rate U) 75.0
FTP Test Pass Rate (%) 0.0
Highway Fuel Economy Test:
Average HFET HC (GM/MI) 2.25
Average HFET CO (GM/MI) 21.44
Average HFET NO (GM/MI) 4.24
3.53
61.7
2.87
50.0
6.3
75.0
0.0
2.25
21.44
4.24
4.35
36.2
3.28
68.8
68.8
75.0
31.3
2.33
13.87
4.75
* Repairs performed by field mechanics.
-------
Table 8.
Portland Element II Sample
(16 1972-1974 Model Year Vehicles
Which Received Only Carburetor Maintenance)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
50970 Miles
300 PPM
3.0 %
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(16 Vehicles)
465.9
5.01
37.
12.
Vehicles Which Fail
Idle Test As Received (15 Vehicles)
As After Garb.
Received Maintenance*
6.3
492.0
5.17
33.3
6.7
0.0
272.0
1.07
80,0
93.3
73.3
Federal Test Procedure:
Average FTP HC (GM/MI) 3.53
Average FTP CO (GM/MI) 61.7
Average FTP NO (GM/MI) 2.87
FTP HC Pass Rate (%) 50.0
FTP CO Pass Rate (%) 6.3
FTP NO Pass Rate (%) 75.0
FTP Test Pass Rate (%) 0.0
Highway Fuel Economy Test;
Average HFET HC (GM/MI) . 2.25
Average HFET CO (GM/MI) 21.44
Average HFET NO (GM/MI) 4.24
3.50
57.8
2.86.
53.3
6.7
80.0
0.0
2.32
19.81
4.29
4.50
35.7
3.27
66.7
73.3
80.0
33.3
2.44
14.12
4.76
* Repairs performed by field mechanics.
-------
Table 9.
Portland Element II Sample
(26 1975-1977 Model Year Vehicles
Which Received Only Carburetor Maintenance)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
29821 Miles
225 PPM
1.0 %
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(26 Vehicles)
248.5
2.92
57.7
15.4
7.7
Vehicles Which Fail
Idle Test As Received (24 Vehicles)
As
Received
264.8
3.15
54.2
8.3
0.0
After Carb.
Maintenance*
102.3
.42
91.7
83.3
75.0
Federal Test Procedure:
Average FTP HC (GM/MI) 2.27
Average FTP CO (GM/MI) 38.6
Average FTP NO (GM/MI) 2.61
FTP HC Pass Rate (%) 38.5
FTP CO Pass Rate (%) 26.9
FTP NO Pass Rate (%) 69.2
FTP Test Pass Rate (%) 11.5
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .67
Average HFET CO (GM/MI) 9.86
Average HFET NO (GM/MI) 3.71
2.39
40.9
2.63
33.3
20.8
66.7
4.2
.69
10.53
3.66
1.70
21.4
2.74
58.
58.
58.
12.5
.64
9.29
3.80
* Repairs performed by field mechanics.
-------
10
Table 10.
Portland Element II Sample
(26 1975-1977 Model Year Vehicles
Which Received Only Carburetor Maintenance)
Average Mileage:
Idle HC Outpoint:
Idle CO Cutpoint:
29821 Miles
300 PPM
3.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(26 Vehicles)
284.5
2.92
73.1
50.0
42.3
Vehicles Which Fail
Idle Test As Received (15 Vehicles)
As After Carb.
Received Maintenance*
339.0
3;95
53.3
13.3
0.0
128.3
.41
93.3
100.0
93.3
Federal Test Procedure:
Average FTP HC (GM/MI) 2.27
Average FTP CO (GM/MI) 38.6
Average FTP NO (GM/MI) 2.61
FTP HC Pass Rate (%) 38.5
FTP CO Pass Rate (%) 26.9
FTP NO Pass Rate CO 69.2
FTP Test Pass Rate (%) 11.5
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .67
Average HFET CO (GM/MI) 9.86
Average HFET NO (GM/MI) 3.71
2.65
40.1
2.38
20.0
26.
73.
6.7
.73
8.44
3.25
1.69
16.9
2.75
60.0
66.7
53.3
6.7
.61
6.90
3.65
* Repairs performed by field mechanics.
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11
Table 11.
Portland Element III Sample
(55 1975-1977 Model Year Vehicles
Which Received Only Carburetor Maintenance)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
37732 Miles
225 PPM
1.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(55 Vehicles)
287.2
3.71
58.2
18.2
12.7
Vehicles Which Fail
Idle Test As Received (48 Vehicles)
As After Carb.
Received Maintenance*
321.4
4.22
58.3
6.3
0.0
101.5
.40
93.8
85.4
79.2
Federal Test Procedure:
Average FTP HC (GM/MI) 2.48
Average FTP CO (GM/MI) 37.2
Average FTP NO (GM/MI) 2.54
FTP HC Pass Rate (%) 30.9
FTP CO Pass Rate (%) 18.2
FTP NO Pass Rate (%) 72.7
FTP Test Pass Rate (%) 10.9
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .68
Average HFET CO (GM/MI) 9.21
Average HFET NO (GM/MI) 3.71
2.66
40.6
2.36
20.8
12.5
77.1
8.3
.70
9.61
3.41
1.60
18.4
2.47
54.2
54.2
68.8
31.3
.48
6.34
3.49
Federal 3-Mode Test:
High Cruise HC (PPM)
High Cruise CO (%)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (%)
Low Cruise NO (PPM)
63.8
.373
1473
100.3
.720
956
65.2
.377
1387
106.2
.792
883
53.2
.275
1309
70.4
.333
909
* Repairs performed by field mechanics,
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12
Table 12.
Portland Element III Sample
(55 1975-1977 Model Year Vehicles
Which Received Only Carburetor Maintenance)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
37732 Miles
300 PPM
3.0 %
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate U)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(55 Vehicles)
287.2
3.71
67.3
40.0
34.5
Vehicles Which Fail
Idle Test As Received (36 Vehicles)
As After Garb.
Received Maintenance*
381.1
4.98
50.0
8.3
0.0
108.2
.46
97.2
100.0
97.2
Federal Test Procedure:
Average FTP HC (GM/MI)
Average FTP CO (GM/MI)
Average FTP NO (GM/MI)
FTP HC Pass Rate (%)
FTP CO Pass Rate (%)
FTP NO Pass Rate (%)
FTP Test Pass Rate (%)
Highway Fuel Economy Test:
Average HFET HC (GM/MI)
Average HFET CO (GM/MI)
Average HFET NO (GM/MI)
2.48
37.2
2.54
30.9
18.
72.
10.9
.68
9.21
3.71
3.01
46.3
2.34
11.1
5.6
77.8
2.8
.77
10.53
3.35
1.70
19.6
2.41
47.2
44.4
69.4
25.0
.51
7.08
3.31
Federal 3-Mode Test:
High Cruise HC (PPM)
High Cruise CO (%)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (%)
Low Cruise NO (PPM)
63.8
.373
1473
100.3
.720
956
70.0
.414
1387
122.4
.992
867
57.2
.294
1304
77.4
.406
866
* Repairs performed by field mechanics.
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13
Table 13.
Portland Element II Sample
(62 1972-1974 Model Year Vehicles)
Average Mileage:
Idle HC Outpoint:
Idle CO Cutpoint:
53735 Miles
225 PPM
1.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(62 Vehicles)
406.7
4.51
38.7
9.7
0.0
Vehicles Which Fail
Idle Test As Received (62 Vehicles)
As After
Received Maintenance*
406.7
4.51
38.7
9.7
0.0
199.3
.95
75.8
61.3
50.0
Federal Test Procedure:
Average FTP HC (GM/MI) 4.07
Average FTP CO (GM/MI) 55.7
Average FTP NO (GM/MI) 3.22
FTP HC Pass Rate (%) 51.6
FTP CO Pass Rate (%) 22.6
FTP NO Pass Rate (%) 66.1
FTP Test Pass Rate (%) 9.7
Highway Fuel Economy Test:
Average HFET HC (GM/MI) 1.97
Average HFET CO (GM/MI) 15.95
Average HFET NO (GM/MI) 5.34
4.07
55.7
3.22
51.6
22.6
66.1
9.7
1.97
15.95
5.34
3.12
32.7
3.31
82.3
72.6
69.4
45.2
1.55
12.20
5.11
* Repairs performed by field mechanics.
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14
Table 14.
Portland Element II Sample
(62 1972-1974 Model Year Vehicles)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
53735 Miles
300 PPM
3.0 %
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(62 Vehicles)
406.7
4.51
59.7
25.8
14.5 .
Vehicles Which Fail
Idle Test As Received (53 Vehicles)
As After
Received Maintenance*
452.1
4.91
52.8
13.2
0.0
198.2
.91
84.9
98.1
83.0
Federal Test Procedure:
Average FTP HC (GM/MI) 4.07
Average FTP CO (GM/MI) 55.7
Average FTP NO (GM/MI) 3.22
FTP HC Pass Rate (%) 51.6
FTP CO Pass Rate (%) 22.6
FTP NO Pass Rate (%) 66.1
FTP Test Pass Rate (%) 9.7
Highway Fuel Economy Test:
Average HFET HC (GM/MI) 1.97
Average HFET CO (GM/MI) 15.95
Average HFET NO (GM/MI) 5.34
4.28
56.3
3.23
50.9
22.6
67.9
9.4
2.09
15.93
5.46
3.22
31.8
3.38
84.9
77.4
71.7
49.1
1.63
12.55
5.28
* Repairs performed by field mechanics,
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15
Table 15.
Portland Element II Sample
(99 1975-1977 Model Year Vehicles)
Average Mileage:
Idle HC Cutpoint:
Idle CO Cutpoint:
26050 Miles
225 PPM
1.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(99 Vehicles)
329.0
3.23
42.4
19.2
7.1
Vehicles Which Fail
Idle Test As Received (92 Vehicles)
As After
Received Maintenance*
351.2
3.45
38.0
13.0
0.0
95.4
.36
94.6
87.0
81.5
Federal Test Procedure:
Average FTP HC (GM/MI) 2.59
Average FTP CO (GM/MI) 37.2
Average FTP NO (GM/MI) 2.47
FTP HC Pass Rate (%) 31.3
FTP CO Pass Rate (%) 24.2
FTP NO Pass Rate (%) 73.7
FTP Test Pass Rate (%) 11.1
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .61
Average HFET CO (GM/MI) 8.46
Average HFET NO (GM/MI) 3.53
2.70
38.9
2.49
28,
20.
71.
7.6
.61
8.61
3.48
1.53
19.5
2.60
64.1
59.8
65.2
31.5
.51
7.68
3.50
* Repairs performed by field mechanics.
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16
Table 16.
Portland Element II Sample
(99 1975-1977 Model Year Vehicles)
Average Mileage:
Idle HC Outpoint:
Idle CO Cutpoint:
26050 Miles
300 PPM
3.0 %
Idle Test;
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(99 Vehicles)
329.0
3.23
55.6
53.5
35.4
Vehicles Which Fail
Idle Test As Received (64 Vehicles)
As After
Received Maintenance*
432.4
4.15
31
28
0.0
99.2
.31
95.3
100.0
95.3
Federal Test Procedure:
Average FTP HC (GM/MI) 2.59
Average FTP CO (GM/MI) 37.2
Average FTP NO (GM/MI) 2.47
FTP HC Pass Rate (%) 31.3
FTP CO Pass Rate (%) 24.2
FTP NO Pass Rate (%) 73.7
FTP Test Pass Rate (%) 11.1
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .61
Average HFET CO (GM/MI) 8.46
Average HFET NO (GM/MI) 3.53
3.12
43.0
2.36
15.6
15.6
73.4
4.7
.68
9.25
3.30
1.57
19.4
2.49
60.9
59.4
62.5
26.6
.54
8.16
3.30
* Repairs performed by field mechanics,
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17
Table 17.
Portland Element III Sample
(108 1975-1977 Model Year Vehicles)
Average Mileage:
Idle HC Outpoint:
Idle CO Outpoint:
35756 Miles
225 PPM
1.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(108 Vehicles)
317.1
3.80
48.1
12.0
7.4
Vehicles Which Fail
Idle Test As Received (100 Vehicles)
As After
Received Maintenance*
338.3
4.09
44.0
5.0
0.0
95
,2
,33
94.0
89.0
83.0
Federal Test Procedure:
Average FTP HC (GM/MI) 2.78
Average FTP CO (GM/MI) 42.0
Average FTP NO (GM/MI) 2.29
FTP HC Pass Rate (%) 22.2
FTP CO Pass Rate (%) 14.8
FTP NO Pass Rate (%) 77.8
.FTP Test Pass Rate (%) 9.3
Highway Fuel Economy Test:
Average HFET HC (GM/MI) .85
Average HFET CO (GM/MI) 12.75
Average HFET NO (GM/MI) 3.27
2.91
44.4
2.18
16.0
11.0
80.0
7.0
.88
13.32
3.08
1.55
20.8
2.40
57.0
53.0
72.0
31.0
.51
8.67
3.29
Federal 3-Mode Test;
High Cruise HC (PPM)
High Cruise CO (%)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (%)
Low Cruise NO (PPM)
77.7
.522
1285
105.8
.767
844
79.6
.540
1226
109.7
.812
801
55.8
.396
1190
64.7
.346
867
* Repairs performed by field mechanics.
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18
Table 18.
Portland Element III Sample
(108 1975-1977 Model Year Vehicles)
Average Mileage:
Idle HC Outpoint:
Idle CO Cutpoint:
35756 Miles
300 PPM
3.0 %
Idle Test:
Average Idle HC (PPM)
Average Idle CO (%)
IHC Pass Rate (%)
ICO Pass Rate (%)
Idle Test Pass Rate (%)
As Received
(108 Vehicles)
317.1
3.80
58.
41,
Vehicles Which Fail
Idle Test As Received (77 Vehicles)
As After
Received Maintenance*
398.7
4.70
41.
18.
28.7
0.0
101.4
.34
97.4
100.0
97.4
Federal Test Procedure:
Average FTP HC (GM/MI) 2.78
Average FTP CO (GM/MI) 42.0
Average FTP NO (GM/MI) 2.29
FTP HC Pass Rate (%) 22.2
FTP CO Pass Rate (%) 14.8
FTP NO Pass Rate (%) 77.8
FTP Test Pass Rate (%) 9.3
Highway Fuel Economy Test;
Average HFET HC (GM/MI) .85
Average HFET CO (GM/MI) 12.75
Average HFET NO (GM/MI) 3.27
3.28
50.3
2.16
6.5
5.2
80.5
1.3
.98
15.24
3.03
1.63
22.7
2.36
51.9
45.
72.
26.0
.55
10.17
3.16
Federal 3-Mode Test:
High Cruise HC (PPM)
High Cruise CO (%)
High Cruise NO (PPM)
Low Cruise HC (PPM)
Low Cruise CO (%)
Low Cruise NO (PPM)
77.7
.522
1285
105.8
.767
844
86.2
.614
1204
125.9
1.003
780
60.3
.449
1171
70.3
.417
819
* Repairs performed by field mechanics.
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19
Table 19.
Effect of Typical I/M Repairs
on NOx Measurements in Portland
(Repairs performed by field mechanics)
Initial Test
Element III
(1975-1977 Vehicles)
Pass (179) Fail (108)
Element II
(1975-1977 Vehicles)
Pass (123) Fail (117)
Element II
(1972-1974 Vehicles)
Pass (113) Fail (95)
FTP NOx (gm/mi)
HFET NOx (gm/mi)
After Maintenance
2.44
3.49
2.29
3.27
2.62
3.72
2.47
3.52
3.42
5.09
3.15
5.13
FTP NOx (gm/mi)
HFET NOx (gm/mi)
Significance of
the Change*
FTP NOx
HFET NOx
2.50
3.45
2.56
3.55
.0274
.2143
.3070
.7543
3.25
4.96
.2280
.4565
* A value of .05 or less indicates a significant change.
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20
Table 20.
Comparison of NOx Measurements
in the Eugene and Portland Element II Samples
(1972-1974 Vehicles)
I/M Area
Initial Test hJ (Portland) N
FTP NOx (gm/mi) 219 3.30 113
HFET NOx (gm/mi) 5.11
1st Quarterly Test
FTP NOx (gm/mi) 202 3.41 98
HFET NOx (gm/mi) 5.04
2nd Quarterly Test
FTP NOx (gm/mi) 197 3.41 93
HFET NOx (gm/mi) 4.75
3rd Quarterly Test
FTP NOx (gm/mi) 187 3.34 88
HFET NOx (gm/mi) 5.13
4th Quarterly Test
FTP NOx (gm/mi) 174 3.16 80
HFET NOx (gm/mi) 5.13
Non-I/M Area
(Eugene)
3.63
5.41
3.70
5.40
3.56
5.18
3.53
5.48
3.40
5.10
Significance of
the Difference*
.0674
.2432
.0877
.1893
.3728
.0905
.3277
.2416
.1952
.9450
* A value of .05 or less indicates a significant difference between the
samples.
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21
Table 21.
Comparison of NOx Measurements
in the Eugene and Portland Element II Samples
(1975-1977 Vehicles)
I/M Area
Initial Test N (Portland) N
FTP NOx (gm/mi) 257 2.55 126
HFET NOx (gm/mi) 3.63
1st Quarterly Test
FTP NOx (gm/mi) 235 2.61 113
HFET NOx (gm/mi) 3.64
2nd Quarterly Test
FTP NOx (gm/mi) 221 2.58 95
HFET NOx (gm/mi) 3.46
3rd Quarterly Test
FTP NOx (gm/mi) 209 2.56 78
HFET NOx (gm/mi) 3.74
4th Quarterly Test
FTP NOx (gm/mi) 199 2.46 75
HFET NOx (gm/mi) 3.74
Non-I/M Area
(Eugene)
2.70
3.76
2.73
3.85
2.53
3.37
2.72
3.72
2.51
3.71
Significance of
the Difference*
.2755
.5327
.4257
.3664
.7501
.6992
.3315
.9368
.7837
.9039
* A value of .05 or less indicates a significant difference between the
samples.
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22
Table 22.
Comparison of NOx Measurements
in the Eugene and Portland Element III Samples
(1975-1977 Model Years)
I/M Area
Initial Test N (Portland) N
FTP NOx (gm/mi) 292 2.40 126
HFET NOx (gm/mi) 3.44
1st Quarterly Test
FTP NOx (gm/mi) 276 2.44 113
HFET NOx (gm/mi) 3.31
2nd Quarterly Test
FTP NOx (gm/mi) 258 2.45 95
HFET NOx (gm/mi) 3.23
3rd Quarterly Test
FTP NOx (gm/mi) 229 2.52 78
HFET NOx (gm/mi) 3.73
4th Quarterly Test
FTP NOx (gm/mi) 228 2.55 75
HFET NOx (gm/mi) 3.61
Non-I/M Area
(Eugene)
2.70
3.76
2.73
3.85
2.53
3.37
2.72
3.72
2.51
3.71
Significance of
the Difference*
.0356
.1130
.0562
.0112
.6135
.5250
.2494
.9530
.8070
.6931
* A value of .05 or less indicates a significant difference between the
samples.
-------
Table 23.
Significance of Changes in
the NOx Measurements Between
Quarterly Tests in Oregon
Init/lst Quarter* 1st Quarter/2nd Quarter* 2nd Quarter/3rd Quarter* 3rd Quarter/Ath Quarter*
Portland Element III
(1975-1977 Vehicles)
FTP NOx .3317
HFET NOx .1298
Portland Element II
(1972-1974 Vehicles)
FTP NOx .0622
HFET NOx .5553
Portland Element II
(1975-1977 Vehicles)
FTP NOx .4480
HFET NOx .9076
Eugene Sample
(1972-1974 Vehicles)
FTP NOx .8758
HFET NOx .9540
Eugene Sample
(1975-1977 Vehicles)
FTP NOx .6537
HFET NOx .8963
.0702
.7773
.5678
.0001
.3618
.0026
.0695
.1206
.0075
.0017
.0594
.0000
.1017
.0002
.8231
.0015
.5480
.0310
.0104
.0190
.3910
.2371
.0023
.9346
.0122
.7325
.1745
.0274
.0249
.9208
* A value of .05 or less indicates a significant difference between the samples.
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