EPA/AA/CTAB/90-04
Technical Report
Durability Testing Of An MIOO-Fueled Toyota LCS-M Carina
Equipped With A Resistively Heated Catalytic Converter
by
Gregory K. Piotrowski
September 1990
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 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.
U. S. Environmental Protection Agency
Office of Air and Radiation
Office of Mobile Sources
Emission Control Technology Division
Control Technology and Applications Branch
2565 Plymouth Road
Ann Arbor, Michigan 48105
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.322,
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
ANN ARBOR. MICHIGAN 48105
SS> 24
OFFICE OF
AIR AND RADIATION
MEMORANDUM
SUBJECT: Exemption From Peer and Administrative Review
FROM: Karl H. Hellman, Chief
Control Technology and Applications Branch"
TO: Charles L. Gray, Jr., Director
Emission Control Technology Division
The attached report entitled "Durability Testing Of An
MIOO-Fueled Toyota LCS-M Carina and A Resistively Heated
Catalytic Converter" EPA/AA/CTAB/90-04 describes the evaluation
of these two systems for exhaust emissions after 6,000 miles of
driving over the AMA Durability Driving cycle.
Since this report is concerned only with the presentation
of data and its analysis and does not involve matters of policy
or regulations, your concurrence is requested to waive
administrative review according to the policy outlined in your
directive of April 22, 1982.
/
Concurrence; ._.- ^-OS-SU*' '^^j ///\ Date;
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Table of Contents
Page
Number
I. Summary 1
II. Background 2
III. Program Design 5
IV. Test Vehicle Description 5
V. Catalytic Converter Description 6
VI. Test Facilities and Analytical Methods 7
VII. Discussion 8
A. Emission Test Results 8
B. Fuel Economy Testing 21
C. Lubricant Analysis 23
VIII.Test Highlights 28
IX. Acknowledgments 29
X. References 30
APPENDIX A - Description of Driving Cycle A-l
APPENDIX B - Test Vehicle Specifications B-l
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I. Summary
Industry representatives have stated that tailpipe
formaldehyde levels from methanol and flexible-fueled vehicles
appear to rise significantly in the first 30,000 miles of
normal vehicle operation. It has been stated that these
emissions typically exceed 15 milligrams per mile in a test
over the Federal test procedure (FTP) after 30,000 miles.
An earlier EPA program accumulated 6,000 miles over the
AMA durability cycle on an MIOO-fueled Toyota LCS-M Carina.
Formaldehyde levels from this vehicle did not substantially
increase during this testing. A resistively heated
palladium:cerium catalytic converter was also recently
evaluated by EPA. Vehicle formaldehyde emissions were held to
a very low 2 milligrams per mile over the FTP with a fresh
catalyst.
This mileage accumulation program referred to above was
repeated here incorporating both the stock manifold
close-coupled platinum:rhodium converter and the resistively
heated palladium:cerium converter in an underfloor location.
Though the underfloor catalyst was not resistively heated
during the mileage accumulation, the goal of this project was
to determine the catalyst's ability to reduce formaldehyde
emissions over time.
Emissions measured as organic material hydrocarbon
equivalent (OMHCE),methanol and carbon monoxide (CO) increased
substantially after 6,000 miles were accumulated. OMHCE and CO
were measured at 0.09 and 1.90 grams per mile over the Federal
test procedure at the end of testing. These levels were still
below the current Federally regulated emission levels of these
pollutants for methanol-fueled vehicles. Aldehyde emissions
rose to 18.8 milligrams per mile over the FTP, up from a low of
3.0 milligrams per mile at the beginning of testing. This
level of 18.8 milligrams per mile still represents an
efficiency of 97 percent from baseline (no catalyst) with
respect to this vehicle.
A severe ^driveability problem occurred with the test
vehicle midway through the project. At that time, the fuel
pump, spark plugs, fuel injectors, lean mixture sensor, and
engine computer were replaced. The extent to which these
problems .and the subsequent repairs may have contributed to the
increase in emissions over time is unknown.
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II. Background
The subject of how emission levels change with accumulated
mileage with methanol engine operation has been discussed on
numerous occasions between U.S. EPA and automotive industry
representatives. Some industry representatives have stated
that their research suggests that a significant rise in
pollutant emissions occurred suddenly, during the first
5,000-15,000 miles of driving. The nature of this increase was
a step-change of considerable magnitude relative to emission
levels noted immediately prior to the change. Increases in
emissions of unburned fuel and formaldehyde were noted; the
vehicles involved were late model, catalyst equipped methanol
vehicles.
Toyota Motor v Corporation recently published a study of
formaldehyde emissions with mileage accumulation on
methanol-fueled vehicles.[1] Toyota noted that engine-out
formaldehyde emissions, particularly from methanol engines
calibrated for lean burn, increased substantially over the
first 30,000 miles of driving. Toyota attributed much of this
increase to combustion chamber deposits of lubricating oil, and
partial oxidation of unburned methanol fuel in the catalytic
converter promoted by increases in engine-out NOx emissions. A
significant catalyst-out decrease in CO efficiency was noted
over 30,000 miles with this study; formaldehyde efficiency
decreased from 97 percent to 92 percent after 30,000 miles.
Aldehyde emissions from flexible-fueled vehicles (FFV) have
been noted to substantially increase as mileage accumulates,
when the FFV's are fueled with M85 (85 percent methanol and 15
percent gasoline).[2]
A large increase in emissions from an MIOO-fueled
Volkswagen Rabbit over 15,000 miles of driving at the EPA Motor
Vehicle Emissions Laboratory (MVEL) was not noted.[3] This
study was limited to an evaluation of engine-out emissions
only; a catalyst was not present on the vehicle for the testing.
Another EPA study examined emission level changes with
catalyst aging on MSS-fueled vehicles.[4] The catalysts were
two noble metal formulations at a lighter loading of 20 grams
per cubic foot OH the substrate.
When tested in a three-way catalyst mode, one formulation
exhibited virtually no change in emission levels after aging
for 12,000 miles. The second formulation had decreases in
efficiency ranging from six percent for emissions measured as
hydrocarbons to 40 percent for NOx emissions, over the FTP
cycle. A number of factors may have combined to influence the
test results and reduce the usefulness of this study,
however.[4]
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A more recent study of emission levels versus mileage
accumulation on a methanol-fueled vehicle involved the
accumulation of approximately 6,000 miles on a Toyota Carina
equipped with the Toyota Lean Combustion System Methanol
(T-LCS-M).[5] The driving was performed under contract at the
Bendix test track located in South Bend, Indiana. The driving
cycle used for this work was the Federal Durability Driving
Schedule.[6] The 6,000 miles were accumulated in two
3,000-mile increments. The vehicle was emission tested by EPA
prior to its initial consignment to South Bend. Upon
completion of the first 3,000-mile increment, the vehicle was
returned to the EPA Motor Vehicle Emission Laboratory (MVEL) in
Ann Arbor, Michigan and emission tested. The car was then
shipped to South Bend for the second 3,000-mile driving
increment. Upon completion of this work, the vehicle was
returned to MVEL for further emissions testing.
Emissions measured as hydrocarbons (HC), organic material
hydrocarbon equivalents (OMHCE),[7] methanol (CH3OH), carbon
monoxide (CO) and formaldehyde (HCHO) over the FTP cycle did
not substantially change during this durability testing.
Emission levels of these pollutants at the completion of this
project were similar to emission levels from several months
prior to its start.
NOx emissions increased slightly over the first 3,000
miles of this project, from 0.89 to 1.01 grams per mile. NOx
was measured at a higher level of 1.42 grams per mile at the
end of the project. The technicians noted a slight misfire at
low-speed cruise conditions during the final 500 miles of
mileage accumulation. This condition was not apparent during
the emissions testing of the vehicle after it was returned to
the EPA laboratory. Immediately after completion of this work,
NOx emissions were measured at 1.04 grams per mile during FTP
testing conducted with this vehicle.
City and highway fuel economies were essentially unchanged
during this project.
EPA has also been concerned about emissions of
formaldehyde from methanol-fueled vehicles for some time. The
major portion "-of formaldehyde (HCHO) emissions from a
catalyst-equipped methanol-fueled vehicle over the FTP cycle
are generated during cold start and warm-up of the catalyst.
These emissions are difficult to control because engine-out
emissions'" are high and catalytic converters have low
conversion efficiency during their warm-up phase of operation.
Heating the catalytic converter at cold start may provide
an emissions reduction benefit over the FTP cycle.[8]
Resistively heating a catalytic converter at cold start may be
a feasible concept if the electrical power requirement for
heating is not excessive and resistive heating is required for
only a limited period of time while the vehicle is operated.
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Resistively heated metal monolith catalytic converters
have been previously evaluated by EPA.[8,9,10,11] The first
testing of this technology [9] on a methanol-fueled vehicle
utilized a platinum/palladium/rhodium mixture similar to
conventional three-way automotive catalysts. FTP Bag 1 levels
of emissions measured as hydrocarbons and formaldehyde were
0.50 and 0.054 grams respectively when the catalytic converter
was resistively heated for 30 seconds at cold start. These
were improvements of 71 and 67 percent respectively over HC and
HCHO levels from the same catalyst in the absence of resistive
heating. The lower Bag 1 emissions translated into weighted
average FTP levels of 0.05 grams per mile for emissions
measured as HC and 5 milligrams per mile for HCHO.
Another recent catalyst evaluation program utilized
similar resistively heated substates but two different active
catalyst formulations.[12,13] These catalysts were:
1. Palladium, with cerium promoter, and
2. A base metal composition.
The exact specifications of the catalyst compositions are
considered proprietary by the catalyst manufacturers, Camet,
Inc. and W. R. Grace. The testing was conducted on a vehicle
equipped with a 1.6 liter, 4-cylinder stoichiometrically
calibrated engine, fueled with M100.
The Pd:Ce catalyst had the highest emission control
efficiencies of either catalyst over the FTP cycle. Emissions
measured as organic material hydrocarbon equivalents (OMHCE)
were reduced to 0.08 grams per mile, and methanol (CH3OH)
emissions were measured at 0.20 grams per mile with this
catalyst. Formaldehyde emissions were reduced to a very low 2
milligrams per mile over the FTP.
The resistively heated catalysts had been evaluated at low
mileage only by EPA. Some industry studies referred to
previously [1,2] have questioned the ability of the current
generation of M85 and flexible fueled vehicles to meet a 15
milligram per mile HCHO standard over the FTP at high mileage.
It was decided to repeat the durability testing project
involving the M100 Carina vehicle mentioned before, [5]
incorporating the resistively heated Pd:Ce catalyst. This
project would age the catalyst for 6,000 miles and provide an
indication of the catalyst's ability to reduce emissions of
formaldehyde over time from a vehicle with high engine-out HCHO
emissions.
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III. Program Design
This project accumulated 6,000 miles on an MIOO-fueled
test vehicle equipped with a resistively heated Pd:Ce catalytic
converter under controlled conditions. The goal of this work
was to note any "step change" behavior in HCHO or methanol
emissions from the test vehicle during this driving.
The test vehicle was equipped originally with a
platinum:rhodium manifold close-coupled catalytic converter;
the resistively heated Pd:Ce catalyst was added in an
underfloor location. Configured in this manner, the car was
tested twice at the MVEL over the FTP and highway fuel economy
test (HFET) cycles. The resistively heated catalyst was heated
for 10 seconds prior to cold start and 50 seconds following
cold start in Bag 1 of the FTP; the catalyst was also heated
for 5 seconds prior to hot start and 30 seconds following hot
start in Bag 3. No resistive heating was applied during the
Bag 2 portion of the FTP or during the HFET cycle tests. The
car was then consigned to ATL for the first increment of
mileage accumulation.
The driving was performed under contract by ATL at the
Bendix test track located in South Bend, Indiana. The 6,000
miles were accumulated in two 3,000-mile increments. The
underfloor converter was not resistively heated during the
driving at ATL; the catalyst was aged in the absence of
resistive heating.
Upon completion of the first 3,000-mile driving increment
the car was to be sent to EPA for emissions testing; following
this testing, the car was to be returned to ATL for the second
3,000-mile driving increment. After the completion of this
second 3,000-mile increment, the car was to be returned to EPA
for final emissions testing.
The driving cycle used for the mileage accumulation was
the Federal Durability Driving Schedule referred to previously
in this report.[6] A description of this driving cycle is
given in Appendix A. The engine oil was to be changed at
1,500-mile increments and the waste oil was saved for metals
analysis. Results from this testing are presented in the
Discussion section.
IV. Test Vehicle Description
The Toyota Lean Combustion System (T-LCS) was described in
a paper appearing in the Japanese Society of Automotive
Engineering Review (JSAE) July 1984. This system made use of
three particular technologies [14] to achieve improvements in
fuel economy as well as to comply with NOx emission levels
under the Japanese 10-mode cycle:
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1. A lean mixture sensor was used in place of an oxygen
sensor to control air/fuel ratio in the lean mixture range;
2. A swirl control valve before the intake valve was
adopted to improve combustion by limiting torque fluctuation at
increased air/fuel ratios; and
3. Sequential fuel injection with optimized injection
timing was used to complement the operation of the swirl
control valve.
The Toyota Lean Combustion System Methanol (T-LCS-M) is
similar to the T-LCS, but has been modified to maximize fuel
economy and driving performance while minimizing pollutant
emissions through the use of methanol fuel. SAE Paper 860247
[15] describes the development of the T-LCS-M system.
Toyota provided EPA with a T-LCS-M system in a Carina
chassis. The Toyota Carina is a right-hand-drive vehicle sold
in Japan, but currently not exported to the United States. The
power plant is a 1587 cc displacement 4-cylinder,
single-overhead camshaft engine. The engine was modified for
operation on methanol in a lean-burn mode, incorporating the
lean mixture sensor, swirl control valve and timed sequential
fuel injection found on the Toyota lean combustion system.
Modifications to the fuel system included the substitution of
parts resistant to methanol corrosion for stock parts.
Detailed test vehicle specifications are provided in
Appendix B.
V. Catalytic Converter Description
The exhaust system of the test vehicle was equipped with
two catalytic converters, a manifold close-coupled converter,
and a resistively heated converter mounted in an underfloor
location. The close-coupled converter was a Toyota stock
converter, utilizing a ceramic monolith substrate. This
catalyst was approximately one liter in volume and contained
platinum:rhodium in proportion and loading similar to most
current OEM three-way catalysts. The underfloor catalyst was a
dual bed configuration, consisting of an unheated metal
monolith substrate and smaller resistively heated metal
monolith. The resistively heated converter was located
approximately 39 inches downstream of the outlet of the exhaust
manifold."*
The metal monolith is resistively heated using a single
12-volt DC battery capable of providing 500-600 cold cranking
amps. Voltage measured across the converter during heating was
typically 9.0-9.5 volts. Current through the converter was
typically measured at 325 and 260 amps at the start and after
one minute of resistive heating. The battery used for EPA's
testing was an additional battery, not the vehicle's battery,
and was located externally to the vehicle.
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No resistive heating was applied to the metal monolith
during the mileage accumulation at ATL. During emissions
testing at the EPA laboratory, the period of resistive heating
was limited 10 seconds prior to and 50 seconds following cold
start (Bag 1), and 5 seconds prior to and 30 seconds following
hot start (Bag 3) in the FTP cycle at 72°F soak conditions.
The dimensions of the underfloor catalyst are similar to
those of typical underfloor catalyst(s) on late model
automobiles. The amperage draw is comparable to the maximum
required by an automotive starter cranking in cold weather,
although starter motors generally do not draw this high level
of current for as long as the resistively heated catalyst does.
The active catalyst on the resistively heated converter
was palladium with cerium promoter. This formulation had been
very effective at controlling formaldehyde emissions from a
methanol vehicle at low mileage conditions.[12,13]
Further details concerning the characteristics of the
resistively heated catalytic converter may be found in
publications [9,16,17] and the sales literature [18] of the
manufacturer, Camet, Inc., a subsidiary of the W. R. Grace
Company.
VI. Test Facilities and Analytical Methods
Emissions testing at EPA was conducted on a Clayton Model
ECE-50 double-roll chassis dynamometer, using a direct-drive
variable inertia flywheel unit and road load power control
unit. The Philco Ford constant volume sampler has a nominal
capacity of 350 CFM. Exhaust HC emissions were measured with a
Beckman Model 400 flame ionization detector (FID). CO was
measured using a Bendix Model 8501-5CA infrared CO analyzer.
NOx emissions were determined by a Beckman Model 951A
chemiluminescent NOx analyzer.
Exhaust formaldehyde was measured using a dinitrophenyl-
hydrazine (DNPH) technique.[19,20] Exhaust carbonyls including
formaldehyde are reacted with DNPH solution forming hydrazine
derivatives. These derivatives are separated from the DNPH
solution by means of high performance liquid chromatography
(HPLC), and quantization is accomplished by spectrophotometric
analysis of the LC effluent stream.
The" procedure developed for methanol sampling and
presently in-use employs water-filled impingers through which
are pumped a sample of the dilute exhaust or evaporative
emissions. The methanol in the sample gas dissolves in water.
After the sampling period is complete, the solution in the
impingers is analyzed using gas chromatograph (GO analysis.[21]
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VII. Discussion
A. Emission Test Results
The resistively heated Pd:Ce catalytic converter was
placed underfloor on the vehicle exhaust system, and the
vehicle was emission tested several times over the FTP and HFET
cycles. The Pd:Ce catalyst was resistively heated during
portions of the FTP as described earlier; no resistive heating
was applied during the HFET testing. Following these initial
tests, the vehicle was consigned to ATL for the first increment
of mileage accumulation.
Table 1 is a summary of emission test results over the FTP
and HFET cycles for this preliminary testing.
The test vehicle had emissions well below currently
regulated limits in all categories. Non-methane hydrocarbons
(NMHC) were not measured at significantly detectable levels
over the FTP. Organic material hydrocarbon equivalents at 0.03
grams per mile were well below the Federal standard of 0.41
grams per mile. Aldehyde emissions in particular were very
low, only 3.0 milligrams per mile over the FTP. NOx was the
only category of pollutants in which the test vehicle did not
have emission levels well below the Federal standard, although
the level of the current NOx standard of 1.0 gram per mile was
easily met. The only pollutant measured in appreciable
concentration under highway driving conditions was NOx, also at
approximately 0.7 grams per mile over the HFET.
The mileage accumulation at ATL was conducted over the AMA
durability cycle. This driving was conducted without incident
for the first 1,000 miles. Several vehicle stalls were noted
by the drivers during this time, but the stalls were not
considered by the technicians to be serious enough to halt the
project. The stalls were noted and the driving continued.
The stalling problem worsened as the driving continued,
however. After approximately 1,300 miles of driving, the
vehicle stalled on the track and the technicians were unable to
immediately restart the engine. It was towed to a garage at
the ATL facility-where it remained overnight. On the following
morning, the vehicle was placed on a chassis dynamometer; the
vehicle ran well, with no driveability problems noted. The
mileage accumulation work was therefore resumed the next day.
The vehicle was fueled with M100 for this mileage
accumulation; no special cold start system was provided.
Because of this, vehicle start temperature was limited to a low
of approximately 55°F. In order to start the vehicle easily,
it was stored in an indoor facility during periods of
inactivity. Prior to driving, the vehicle was started indoors
and immediately driven onto the test track where the driving
was performed.
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Table 1
M100 Carina With Two-Catalyst System
Emission Test Results, FTP Cycle
Testing Prior To Initial Vehicle Consignment
Date
Jan 1990
HC*
(q/mi)
0.02
NMHC
(q/mi)
0.00
OMHCE
(q/mi)
0.03
CH30H
( q/mi )
0.06
CO
(q/mi)
0.75
NOx
(q/mi)
0.70
Aide.
(mg/mi)
3.0
HFET Results
Date
Jan 1990
HC*
(q/mi)
0.00
NMHC
(q/mi)
0.00
OMHCE
( q/mi )
0.00
CH3OH
(q/mi)
0.01
CO
(q/mi)
0.00
NOx
(q/mi)
0.69
Aide.
(mq/mi)
0.0
HC measured with propane calibrated FID.
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Cold outdoor temperatures were experienced during this
testing, which occurred in February 1990. It is possible that
these cold ambient conditions adversely affected the
driveability of this MIOO-fueled vehicle. No attempt was made
at that time, however, to determine whether cold outdoor
temperatures on a particular day affected such parameters as
coolant temperature or oil temperature during driving.
At approximately 2,563 miles the stalling problem worsened
appreciably. The technicians determined that the vehicle was
not sufficiently reliable to ensure completion of the first
3,000-mile driving increment. The vehicle was therefore
returned to MVEL on March 12, 1990 for diagnosis and repair.
Only one problem/incident specifically related to the
underfloor catalyst was noted during driving at this time. A
leak was noted behind the converter. The tailpipe was removed,
and a new flange was placed on the pipe to provide a better
mating surface to the catalyst flange. The leak had occurred
at the downstream joint of the converter.
Upon arrival at MVEL, the vehicle was test driven over the
FTP cycle. The stalling problem noted at ATL was also noticed
by EPA technicians. On the advice of Toyota engineering
personnel, the vehicle fuel tank was drained and the in-tank
fuel pump was replaced. This action did not remedy the idle
stall problem, however. The fuel injectors were then replaced
and the spark plugs cleaned. The vehicle driveability then
appeared to have improved enough to conduct emissions testing.
A sample of the fuel in the vehicle tank was taken when
the tank was drained for the replacement of the pump. This
sample was tested twice at MVEL for water content under ASTM
standard "Test Method for Determination of Ct to C4
Alcohols and MTBE in Gasoline Using Gas Chromatography"
(D4818-88) Vol. 5.01, 1988. The samples should have consisted
of nearly 100 percent alcohol due to the use of M100 fuel.
Instead, alcohol contents of 85 and 88 percent respectively
were measured for the two samples.
The remainder of the fuel sample was sent to a contract
laboratory for -Karl Fischer titration analysis (ASTM D1744).
We were concerned that possible water contamination of the fuel
might have occurred. The analysis indicated only 511 ppm water
content in the fuel, however.
It is possible that fuel contamination or even misfueling
might have occurred during the mileage accumulation, based on
the above. Very little fuel remained in the ATL M100 supply
when the test vehicle was returned to EPA. New M100 was
ordered at this time, and the remaining fuel was disposed of.
We were unable, therefore, to sample the M100 used by ATL when
the driveability problems arose.
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Table 2 contains a summary of the testing over the FTP
cycle performed at 2,563 miles into this project. The first
category under "Description of Testing" is a test with no
resistive heating applied to the catalyst, after the
replacement of the fuel pump and injectors. The second
category repeats this testing with the underfloor catalyst
resistively heated as described earlier.
Resistive heating significantly increased the efficiency
of the underfloor catalyst with respect to methanol, HC and
formaldehyde emissions. These emissions are reduced roughly 50
percent by catalyst resistive heating. CO was not affected by
catalyst resistive heating. Even with a lean burn
methanol-fueled vehicle, it may be necessary to add additional
air in front of the converter to reduce CO levels during warm
up.[11] The reduction in NOx levels was unexpected given our
previous experience with this heated converter.[12,13]
The emission levels of most measured pollutants appeared
to have significantly changed from the start of the program to
the 2,563-mile point. Most emission levels appeared to have
doubled with CO and aldehyde emissions increasing more than 100
percent. The aldehyde increase, from 3.0 milligrams per mile
increasing to 8.3 milligrams per mile, was most noticeable.
During this testing another driveability problem was noted
by the EPA technicians. Stalls in the latter part of the FTP
(Bags 2 and 3) were noticed, occurring two to three times per
test. Though these stalls were not occurring during the most
critical portion of the test with respect to emissions (Bag 1
cold start), it was possible that this driveability problem
might have materially affected the emissions profile. The
problem was described to Toyota, and their assistance with
diagnosis and repair was again requested.
Toyota provided EPA with a new lean burn sensor and
computer PROM for the Carina vehicle. These parts were
installed, and the driveability problems ceased. The FTP tests
were repeated with the underfloor catalyst resistively heated
as referred to previously. The third category in Table 2
provides results from this testing.
*• **
Emissions of HC, methanol and aldehydes did not change
significantly as a result of these latest modifications.
Emissions of CO and NOx however, decreased approximately 40 and
50 percent respectively, from levels measured immediately
before the lean burn sensor and PROM were replaced.
Table 3 contains data in grams per Bag 1 from FTP testing
with the underfloor catalyst resistively heated. Testing prior
to mileage accumulation is described together with testing at
2,563 miles after replacement of the fuel injectors and fuel
pump, and finally after replacement of the lean burner sensor
and engine computer.
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Table 2
M100 Carina With Two Catalyst System
Emission Test Results, FTP Cycle
Testing At 2,563 Miles
Description
of Testing
HC*
(q/mi)
New pump, 0.11
injectors,
no resistive heat
New pump, 0.05
injectors,
resistive heat
to catalyst
New pump, 0.05
injectors,
LB sensor, ECU,
resistive heat
to catalyst
NMHC OMHCE CH30H CO NOx Aide.
(q/mi) (q/mi) (q/mi) (q/mi) (q/mi) (mq/mi)
0.01 0.15 0.26 2.04 0.97 20.3
0.00 0.07 0.13 2.14 0.66
0.00 0.06 0.11 1.34 0.34
8.3
8.5
HC measured with propane calibrated FID.
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Table 3
Bag 1 Emissions From FTP Cycle
FTP Cycle, Testing at 2,563 Miles
Description
of Testing*
Prior to
mileage
accumulation
2,563 miles,
new pump,
injectors
2,563 miles,
new pump,
injectors,
sensor, ECU
HC** NMHC OMHCE CH30H CO NOx Aide.
(g/bag) (g/bag) (g/bag) (g/bag) (g/bag) (g/bag) (mg/bag)
0.25 0.04 0.33 0.55
9.39 2.85
33.9
0.58 0.04 0.79 1.42 15.81 2.66 111.5
0.66 0.11 0.87 1.47 14.08 1.92 109.8
* Underfloor catalyst resistively heated.
** HC measured with propane calibrated FID.
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The trends in emissions in Bag l follow those for the
weighted FTP noted earlier. Emissions measured as organic
material hydrocarbon equivalents, methanol and aldehydes in Bag
1 increased significantly after 2,563 miles. The replacement
of the lean burn sensor and engine computer did not
significantly effect tailpipe emissions over Bag 1. CO and NOx
Bag 1 levels appeared to be reduced slightly by the replacement
of these components.
Driveability was much improved as a result of these final
changes; the stalling problem, either at hot or cold idle, was
not noticed. The driveability had improved enough to permit
the completion of the durability driving, so the vehicle was
returned to the ATL facility.
Driving continued at the test track without serious
incident, the only driveability concern being an occasional
stall followed by a quick restart. The vehicle was returned to
MVEL following the completion of the mileage accumulation at
the end of June 1990.
Table 4 contains a summary of the test data prior to the
start of driving, at the 2,563-mile point, and at the
completion of the project. Emissions measured as NMHC, OMHCE,
and of methanol are presented in graphical form in Figure 1.
Figure 2 presents the same information for CO, NOx and aldehyde
emissions. Aldehyde emissions, in milligrams per mile, have
been divided by a factor of 10 for easier inclusion on Figure
2. The testing at the 2,563-mile point referred to was
conducted after all of the diagnostic and repair work referred
to previously was completed. No attempt is made to determine
the effect of these repairs on the comparability of emission
levels between the 2,500-mile point and the completion of the
project.
NMHC emissions, possibly associated primarily with lube
oil emissions, were uniformly low throughout the duration of
the project. Emissions of OMHCE and methanol steadily
increased with accumulated mileage, however. Emissions of CO
increased steadily over time also; after the repair work, CO
levels continued to increase. NOx was reduced to a low of
about 0.4 grams",per mile at the time of the engine repairs;
this level increased to approximately 0.5 grams per mile at the
end of the project. Aldehydes increased steadily, exceeding 18
milligrams per mile over the FTP at the end of the project.
The 18.8"-milligrams per mile level at the end of testing
exceeds the 15 milligrams per mile standard for model year 1993
methanol vehicles proposed by the California Air Resources
Board. [22] The 18.8 milligrams per mile over the FTP still
represents an efficiency of 97 percent with respect to baseline
emissions of 570 milligrams per mile with this vehicle.[23]
-------
-15-
Table 4
Emission Test Results, FTP Cycle
Summary After Completion of Testing
Test
Date
Jan 1990
start of
testing
April 1990
2,563 miles
May 1990
6,000 miles
HC*
(q/mi)
0.02
0.05
0.07
NMHC
(q/mi)
0.00
0.00
0.01
OMHCE
(q/mi)
0.03
0.06
0.09
CH3OH
( q/mi )
0.06
0.11
0.16
CO
(q/mi)
0.75
1.34
1.90
NOx
(q/mi)
0.70
0.34
0.48
Aide.
(mq/mi)
3.0
8.5
18.8
HFET Results
Test
Date
Jan 1990
April 1990
May 1990
HC*
(Q/mi)
0.00
0.00
0.00
NMHC
(q/mi)
0.00
0.00
0.00
OMHCE
(q/mi)
0.00
0.00
0.01
CH30H
(q/mi)
0.01
0.01
0.01
CO
( q/mi )
0.00
0.03
0.09
NOx
(q/mi)
0.69
0.14
0.22
Aide.
(mq/mi)
0.0
0.5
1.7
HC measured with propane calibrated FID.
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-16-
Figure 1
M100 Carina With Heated Catalyst
Emission Results, FTP Cycle
NMHC (g/mi)
OMHCE (g/mi)
CH3OH (g/mi)
Emission Levels
0.15 -
0.06 -
o -
0 mi
* Not to scale
2563 mi
Test Intervals*
J
6000 mi
Figure 2
M100 Carina With Heated Catalyst
Emission Results, FTP Cycle
CO (g/mi)
NOx (g/mi)
Alde.<
Emission Levels
0 mi
• mg/mi divided by 10
•• Not to scale
2663 mi
Test Intervals**
J
6000 mi
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-17-
The general increase in pollutant emissions noted here
could have been caused by a number of factors. For example,
the driveability problems noted earlier could be a source of
higher HC and CO emissions. It is possible that other
problems, not identified during the diagnostic and repair work
performed midway in the project, contributed to the higher
emissions noted at the end of the project. A new methanol-
tolerant fuel pump will soon be supplied to EPA by Toyota.
Toyota believes that the replacement pump presently on the
Carina may be subject to deterioration that would adversely
affect the performance of the engine.
Deterioration of the catalytic converter systems could
also have occurred and caused an increase in pollutant emission
levels. This deterioration could have occurred in several
different ways. For example, the manifold close-coupled
converter could have been subjected to significant thermal
shock if engine misfire occurred. A small amount of black
carbon matter was found on the face of the resistively heated
catalytic converter after the project. It is possible that
conditions in front of the converter together with the choice
of active catalyst combined to induce coking. This reaction
would be detrimental to the catalyst, eventually poisoning and
deactivating it.
Figures 3 and 4 give FTP emissions over time for several
pollutant categories for the M100 Carina equipped with the
stock manifold close-coupled catalyst. The testing reported
was conducted without utilizing the resistively heated
underfloor Pd:Ce converter. The testing referred to as August
1990 was conducted after the completion of the mileage
accumulation program.
In general, emissions from the test vehicle have
approximately doubled during the last 8,000 miles of driving
(much of this mileage being the durability work reported on
here). Emissions measured as OMHCE and methanol more than
doubled during this time, to 0.19 and 0.34 grams per mile.
Formaldehyde emissions roughly doubled to 25 milligrams per
mile. CO emissions have quadrupled from the December 1986
levels. NOx emissions are presently at approximately similar
levels to those^vhen the car was first received from Toyota in
1986. During this time, NOx has varied from a high of 1.42
grams per mile in June 1990. These swings may have been caused
in large part by modifications and engine repairs to correct
perceived "driveability problems.
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-IB-
Figure 3
M100 Carina Without Camet Catalyst
Emission Results, FTP Cycle
OMHCE (g/mi)
CH3OH (g/mi)
Emission Levels
DEC 88
OCT 88 MAR 89
Test Intervals**
AUQ 90*
« Denotes end of current effort
** Not to scale
Figure 4
M100 Carina Without Camet Catalyst
Emission Results, FTP Cycle
i CO (g/mi)
NOx (g/mi)
Aide.
Emission Levels
DEC 86 OCT 88 MAR 89
Test Intervals***
* mg/mi divided by 10
•• Denotes end of current effort
••• Not to scale
AUQ 90"
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-19-
At present, it is difficult to determine quantitatively
what portion of the recent increase in emission levels is due
to mechanical troubles yet occurring with the vehicle. The
fuel pump on the vehicle will be replaced with a new
methanol-tolerant pump when it is received from Toyota.
Subsequent emissions testing will indicate whether this
component was a cause of higher emission levels.
One way to determine whether the resistively heated
underfloor catalyst had deteriorated and contributed to higher
emissions is to test this catalyst on a vehicle other than the
LCS-M Carina. The same resistively heated Pd:Ce converter had
been evaluated on a stoichiometrically calibrated MlOO-fueled
vehicle just prior to the work described in this report. The
results from testing on this stoichiometrically calibrated
vehicle have been previously reported.[12,13] This previous
testing was recent enough to attempt a comparison of results
from previous and current testing. In addition, the
stoichiometrically calibrated vehicle had not been used for a
project since the testing described in [12,13]; no
modifications had been made to the vehicle, nor had it been
operated under severe conditions.
The stoichiometrically calibrated vehicle was a 1981
Volkswagen Rabbit sedan equipped with a 1.6 liter engine and
fueled with M100. The characteristics of this vehicle are
given in detail in [12]. The resistively heated Pd:Ce catalyst
was removed from the Carina and placed on the Rabbit in the
same underfloor location as the testing described in [12,13].
The Rabbit was emission tested twice over the FTP cycle. The
catalyst was resistively heated in the same manner as described
in this earlier testing [12,13] and in this report. Results
from this current testing are compared with testing conducted
on this vehicle in December 1989 in Table 5. Test results over
the FTP cycle are presented, together with emission levels in
grams from the Bag 1 portion of the tests.
Current levels of OMHCE and CHjOH were much higher than
the very low levels measured during December 1989. At 0.29
grams per mile, current OMHCE were still below the 0.41 grams
per mile level mandated in the Federal light-duty methanol
vehicle regulations. CO was still below the Federally
regulated emission levels of 3.4 grams per mile, but the
current emissions level was three times the magnitude of the
December 1989 level. NOx also rose slightly, to 1.0 gram per
mile during the current testing.
The emissions category showing the greatest percentage
increase over time was aldehyde. Very low aldehyde emissions
of 2.0 milligrams per mile were measured with this catalyst
when it was fresh. After 6,000 miles on the MlOO-fueled lean
burn vehicle, the catalyst was capable of reducing aldehyde
emission levels to only 33 milligrams per mile over the FTP.
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-20-
Table 5
M100 Volkswagen Rabbit With Camet
Pd:Ce Converter Emissions Testing, FTP Test Cycle
Date
December 1989
August 1990
Date
December 1989
August 1990
NMHC
(q/mi)
0.01
0.02
NMHC
Ifll_
0.04
0.37
OMHCE
( q/mi )
0.08
0.29
Baq
OMHCE
1.19
3.98
CH30H
(g/mi)
0.20
0.55
1 Only
CH30H
(
-------
-21-
Bag 1 emissions were uniformly higher when the most recent
tests were compared to testing with a fresh catalyst. OMHCE
emissions during the most recent testing were over three times
as high as testing during December 1989. Aldehyde emissions in
particular had increased in magnitude significantly, to
approximately 406 mg over Bag 1.
No driveability problems with the Volkswagen Rabbit were
noted during the August 1990 testing; the car performed very
well. No problems with catalyst resistive heating were noted
during this testing. Baseline (no-catalyst) emission levels
were not measured during August 1990, because there were no
comparable emissions data available from December 1989.
The resistively heated Pd:Ce catalyst was removed from the
Rabbit vehicle following the completion of testing and returned
to W. R. Grace. This catalyst will be analyzed by Grace to
determine whether catalyst deterioration has occurred, and if
so, what the mechanism of deactivation was.
B. Fuel Economy Testing
Fuel economy test results are presented in Table 6. City,
highway, and composite methanol MPG figures are presented as
well as gasoline equivalent composite fuel economy. Fuel
economy data is in chronological order, since the test vehicle
was received from Toyota, Japan, is also presented for
comparison.
The gasoline equivalent fuel economy values are based on
adjusting for the energy content difference between gasoline
and methanol. The nominal energy content of gasoline has been
established at 18,507 BTU/lb [24] yielding 114,132 BTU/gallon.
Methanol at 8,600 BTU/lb is 56,768 BTU/gallon. The adjustment
for M100 fuel based on fuel energy is:
Gasoline equivalent adjustment = Energy of gasoline
Energy of methanol
Dividing the energy of gasoline:
Gasoline equivalent adjustment = 2.0105
FTP fuel economy was essentially unchanged from previous
levels by this project. Fuel economy increased slightly during
the proje'Ct from 18.3 MPG over the FTP at project start to 19.0
MPG at the completion. This 19.0 methanol MPG was the highest
city fuel economy measured to date with the test vehicle, but
this was only 0.3 MPG higher than the values recorded when the
vehicle was first delivered to EPA. We do not know the effect
on fuel economy of each of the modifications that were made to
the vehicle midway in the project (replacement of plugs, lean
mixture sensor, ECU, and fuel pump).
-------
-22-
Table 6
Toyota LCS-M Carina
Fuel Economy Test Results
Date
September 1986
December 1986
July 1987
July 1988
October 1988
March 1989
January 1990*
May 1990**
June 1990***
City
MPG
18.7
17.9
17.0
18.2
18.6
18.0
18.3
18.6
19.0
Highway
MPG
N/A
25.7
24.4
23.7
26.5
25.4
26.1
26.2
27.3
Composite
MPG
N/A
20.7
19.7
20.3
21.5
20.7
21.1
21.4
22.0
Gasoline
Equivalent
Composite MPG
N/A
41.6
39.6
40.8
43.2
41.6
42.4
43.0
44.2
* Start of current program.
** Midway point of current program.
*** End of current program.
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-23-
Highway fuel economy appears to follow city MPG. A small,
yet measurable increase in highway fuel economy was noted over
the current project. The 27.3 MPG highway fuel economy at the
end of the project combined with the higher 19.0 methanol city
MPG to give a gasoline equivalent composite fuel economy of
44.2 MPG. While this was the highest gasoline equivalent
composite fuel economy yet recorded with this vehicle, it was
yet only marginally higher than the 43.2 MPG measured in
October 1988.
C. Lubricant Analysis
Published reports have indicated that the use of methanol
fuel may result in engine wear rates that exceed those of
comparably sized gasoline engine, when conventional lubricants
are used.[25,26] Typically, this increased wear is described
as having occurred in the top piston ring and upper cylinder
bore area.[27]
Toyota specified an oil change interval of 3,000 miles
when the Carina was delivered to EPA for evaluation. During a
previous mileage accumulation effort involving this vehicle,
the oil was changed every 1,500 miles and analyzed for wear
metals content.[5] For the effort described here, the engine
oil was also to be changed at 1,500-mile intervals and samples
were to be taken for metal content.
The first sample was taken after 1,500 miles had been
driven. The vehicle had been driven for an additional 850
miles prior to the start of the program, for a total of 2,350
miles with the same oil. We chose to not change the oil at the
beginning of the program to determine what the effect of a more
normal oil change interval would be on contaminant metals
concentrations.
The second oil sample was taken after the vehicle was
returned to MVEL for engine diagnostics and repair. A complete
1,500-mile increment was not driven between the first oil
change and the return of the vehicle to MVEL. It proved
convenient to change the oil while the vehicle was at MVEL, so
this sample is referred to here as being taken after only 1,063
miles of driving-on the oil that was sampled.
The third sample was taken after a cumulative total of
4,500 miles had been driven on the vehicle during the project.
This third sample therefore was taken after approximately 1,936
miles had been accumulated since the second sample. The fourth
and final sample was drawn after the final 1,500-mile driving
increment.
-------
-24-
The oil samples were analyzed from FRAM through their
FRAM/CODE oil analysis program. This analysis includes a
spectrographic metals test as well as a series of physical
tests to determine viscosity, fuel dilution and solids content
of the oil. This information was used as an indicator to
determine whether abnormal wear of parts was occurring.
Results from analyzing these individual oil samples are
presented in Table 7. The wear metals data presented here was
limited to those metals which indicated higher than normal
parts wear or related to major engine components.[28] The FRAM
program made the determination that higher than normal wear was
occurring.
The wear metals data is presented in two formats. First,
wear metals content of the sample taken is presented in units
of parts per million (ppm) by weight. Because the oil was
sampled after different driving intervals and the oil was
changed when sampled, this length of driving time may have
influenced the metals content of the oil. For example, the
first sample was taken after 2,358 miles of driving, and the
oil was changed at sampling time. Barring unusual driving
conditions or engine trouble, it may be logical to expect that
the metals content of the second sample, taken after driving
1,063 miles, might be lower due to the shorter period of wear.
The data is therefore presented also in terms of ppm of metal
per mile driven with the oil sampled at that time.
Oil sample number 2 exhibited somewhat different levels of
wear metals per mile than the other samples. This situation
may have been related to the driveability problems which became
very noticeable at that time. Water contamination of the oil
was noticed at this time; this contamination was not noticed in
the other samples taken. The source of this water
contamination is unknown. This could have been caused by fuel
contamination, excessive blowby, or cold ambient temperatures
which may have hindered the functioning of the PCV system. The
following two oil samples indicated less wear generally with
respect to the number of miles traveled with the same oil. For
these reasons, the second oil sample may not be a good
indicator of the average wear metals levels to the expected
from a methanol-vehicle under normal wear conditions.
Higher than normal concentrations of iron were indicated
in three of the four oil samples. Higher concentrations of
iron are-normally present where increased wear in the cylinders
and of gears is occurring. Elevated levels of aluminum were
also found in the same three samples. Aluminum is generally
present in oil due to wear of pistons and bearing surfaces.
-------
-25-
Table 7
Metal Contaminants In Lube Oil Samples
(data given in PPM and PPM/mile)
Metal/Other
Contaminant
Iron
Aluminum
Chromium
Copper
Lead
Water
Sample 1
2,358 miles
72V0.031
20V0.008
22V0.009
6 /0.003
37V0.016
—
Sample 2
1,063 miles
67V0.063
13V0.012
22*/0.021
4 70.004
25*70.024
0.1**
Sample 3
1,936 miles
75*70.039
18*70.009
30*70.015
4 70.002
14 70.007
—
Sample 4
1,500 miles
37/0.025
6/0.004
17/0.011
2/0.001
16/0.011
—
* Levels flagged by FRAM as of moderate concern.
** Water level greater than 0.1 volume percent measured.
-------
-26-
Elevated concentrations of chromium, probably from piston
rings, were noted in the first three oil samples. Higher than
normal concentrations of lead were also noted in the first two
samples. Because of the use of M100, the lead probably was not
related to the fuel vapors. Higher levels of lead, when
accompanied by elevated concentrations of aluminum, may be an
indicator of bearing wear. Copper levels, however, were within
the range considered to be normal by FRAM; copper is also
commonly associated with bearing surfaces.
Pefley, in SAE Paper 831704, [29] provides oil analysis
wear metals data from a small fleet of methanol-fueled sedans.
These vehicles were powered by 1.6-liter Volkswagen engines;
vehicle weight and engine displacement were similar to the
Toyota Carina test vehicle used in this project. The oil used
in Pefley's work was a commercially available SAE 20W-40 SF-CC
oil. The oil was sampled every 1,000 miles and was changed at
3,000-mile intervals. Pefley's vehicles were driven from 7,000
to 17,000 miles; oil sampling did not occur during the first
3,000 miles of break-in driving. Numerical averages of
Pefley's wear metals data are presented in Figures 5 and 6.
Also presented in Figures 5 and 6 is wear metals data from
the previous 6,000-mile durability effort with this test
vehicle.[5] These samples were taken at 1,500-mile increments;
the driving was conducted over the same driving schedule as the
present effort described here. The oil used in this earlier
testing was the same specially blended lubricant for
methanol-fuelec vehicles. Figures 5 and 6 also contain wear
metals data from the first, third, and fourth samples taken
during the current effort. The data from the second sample is
not included here, as this sample was taken when the vehicle
was experiencing obvious driveability problems. The data
presented in Figures 5 and 6 is limited to metals
concentrations in ppm as presented in the earlier reports
quoted from here.[5,29]
The iron concentrations measured during the present
testing were roughly comparable to the levels measured during
the earlier durability effort [5] if the extended driving of
the first two samples is considered. The last sample, 37 ppm,
is a considerably improvement over the 49 ppm average measured
during.[5] All of the samples from the MIOO-fueled Toyota
vehicle had much lower iron levels in their oil than the
methanol-fueled Volkswagen vehicles used by Pefley.[29]
Aluminum concentrations from the first and third samples
of the current effort were similar in magnitude to those of the
previous durability effort [5] when the mileage over 1,500
miles is considered. The last sample of the current effort was
taken after driving 1,500 miles; at 6 ppm, this concentration
of aluminum was less than one half of that measured during the
previous durability experiments.[5] The methanol-fueled
Volkswagen vehicles used in SAE Paper 831704 exhibited
considerably higher aluminum wear metals concentration than on
the MlOO Toyota vehicle.
-------
-27-
Figure 5
Oil Analysis - Metal Contamination
Comparison With Published Data
Iron (Fe)
Aluminum (Al)
J
PPM By Weight
831704* Previous** 2358 mi*** 1936 mi***
Source Of Sample
• From SAE 831704
•• From CTAB 89-03
**• Present Work Described Here
1600 mi**
Figure 6
Oil Analysis - Metal Contamination
Comparison With Published Data
I Chromium (Or) RMS! Copper (Cu) I
PPM By Weight
831704* Previous** 2368 mi*- 1936 mi***
Source Of Sample
* From SAE 831704
•• From CTAB 89-03
••• Present Work Described Here
1600 mi***
-------
-28-
Chromium levels in oil from Carina testing could not be
correlated with miles driven on the same oil. The 30 ppm of
chromium measured with the oil used for 1,936 miles was higher
than the 22 ppm measured in oil that was run in the engine for
2,358 miles. The final 1,500-mile sample taken during the
present work had a chromium concentration of only 17 ppm. This
was considerably below most other measured levels and the data
presented in SAE Paper 831704.
Concentrations of copper were measured at relatively low
levels during the present work as well as during the past
durability project.[5] Though copper concentrations appeared
to increase with increasing mileage experienced by the oil
during the present work, the final sample over 1,500 miles had
less than half the level measured for 1,500 miles in the
previous project. The copper concentration of 2 ppm from this
final sample was also substantially below the 19 ppm measured
by Pefley during his work.
No attempt to relate metals wear rates to engine condition
or emissions is made here. We did not examine the condition of
cylinder walls, bearing surfaces, piston crowns, etc. either
before or after the current effort. A limited number of oil
analyses were made, and these did not occur at evenly spaced
intervals. Gasoline control vehicles were not used and the
analysis was limited to a single test vehicle. The data
presented here suggests that some accelerated engine wear with
respect to expected gasoline vehicle wear may be occurring in
the test vehicle, according to FRAM. While the possibility of
advanced wear rates should be a concern of those responsible
for methanol vehicle fleets, no attempt was made to reduce them
here, through the use of special lubricant additives or special
methanol-tolerant metal surfaces.
VIII.Test Highlights
1. Emissions of OMHCE, CH,OH, and CO over the FTP
increased substantially after 6,000 miles of driving over the
AMA durability cycle. OMHCE at 0.09 and CO at 1.90 grams per
mile at the end of testing were still below current Federally
regulated emission levels for methanol vehicles.
2. NOx emissions over the FTP dropped to a very low
0.34 grains per mile after a driveability problem was
investigated and corrected midway in the program.
3. Aldehyde emissions rose to 18.8 milligrams per mile
at the end of testing, up from a very low 3.0 milligrams per
mile at the start of the program. This 18.8 milligrams per
mile over the FTP still represents an efficiency of 97 percent
from baseline with respect to this vehicle.
-------
-29-
4. City and highway fuel economies were essentially
unchanged by the project. The gasoline equivalent composite
fuel economy of 44.2 MPG measured at the end of testing was
similar to the 43.2 MPG measured during October 1988.
5. Oil samples were taken four times from the test
vehicle during this project and analyzed for wear metals
concentrations. According to FRAM, Inc. standards, three of
the samples indicated higher than normal concentrations of
iron, aluminum, and chromium. Lead concentrations were judged
by FRAM to be higher than normal in two samples. A significant
amount of water was found to be present in the lube oil during
a period in which severe driveability problems with the test
vehicle were noted.
The extent to which out of the ordinary driveability
problems may have affected these wear metals concentrations is
unknown. The final sample, taken after 1,500 miles of
relatively incident-free driving, showed normal concentrations
of the metals mentioned above; no category was flagged as
indicative of abnormal wear rates. More testing over a longer
period of vehicle operation should be conducted to determine
whether this methanol-fueled engine is experiencing metal wear
rates higher than those expected from a comparable
gasoline-fueled engine.
IX. Acknowledgments
The Toyota Carina test vehicle was loaned to EPA for use
with .alternative fuels research programs by the Toyota Motor
Co., Ltd. The MIOO-fueled Rabbit vehicle has been loaned to
EPA by Volkswagen of America. The.resistively heated catalyst
was provided by Camet, Inc., a subsidiary of W. R. Grace.
FRAM, Inc., a subsidiary of Allied Signal, provided the
lubricant analysis. The engine oil, specially blended for use
with methanol vehicles, was provided by Lubrizol.
The author appreciates the efforts of James Garvey, Robert
Moss, and Steve Half yard of the Test and Evaluation Branch
(TEB) who conducted the emissions testing and assisted with the
driveability problem diagnosis and repair. John Shelton, also
of TEB, acted a£- the EPA contract officer and liason with ATL
for this effort.
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-30-
X. References
1. "Study of Mileage-Related Formaldehyde Emission from
Kethanol-Fueled Vehicles," Tsukasaki, Y. , et al., SAE Paper
900705, February 1990.
2. "A View of Flexible Fuel Vehicle Aldehyde
Emissions," Nichols, R. J., et al. , SAE Paper 881200, August
1988.
3. Results of Methanol Catalyst Testing Analyzed for
Trends In Baseline Variance, Memorandum, Piotrowski, G. K.,
OAR/OMS/ECTD/CTAB, October 24, 1985.
4. "Durability of Low Cost Catalysts for
Methanol-Fueled Vehicles," Heavenrich, R. M. , R. I. Bruetsch,
and G. K. Piotrowski, EPA/AA/CTAB/87-01, October 1987.
5. "Durability Testing of a Toyota LCS-M Carina,"
Piotrowski, G. K., EPA/AA/CTAB/89-03, June 1989.
6. Federal Durability Driving Schedule, Appendix IV,
Part 86, 40 CFR, Chapter 1.
7. Definitions, 40 CFR Part 86.092-2, Federal Register,
Vol. 54, No. 68, Tuesday, April 11, 1989.
8. "Resistive Materials Applied to Quick Light-Off
Catalysts," SAE Paper 890799, Hellman, K. H., et al., March
1989.
9. "Evaluation of a Resistively Heated Metal Monolith
Catalytic Converter on an M100 Neat Methanol-Fueled Vehicle,"
Blair, D. M. and G. K. Piotrowski, EPA/AA/CTAB/88-08, August
1988.
10. "Evaluation of a Resistively Heated Metal Monolith
Catalytic Converter on a Gasoline-Fueled Vehicle," Piotrowski,
G. K., EPA/AA/CTAB/88-12, December 1988.
11. "A Resistively Heated Catalytic Converter With Air
Injection For Oxidation of Carbon Monoxide and Hydrocarbons At
Reduced Ambient Temperatures," Piotrowski, G. K., EPA/AA/CTAB/
89-06, September 1989.
12. I "Evaluation of Resistively Heated Metal Monolith
Catalytic Converters On An M100 Neat Methanol-Fueled Vehicle,"
Part II, Piotrowski, G. K., EPA/AA/CTAB/89-09, December 1989.
13. "Recent Results from Prototype Vehicle and Emission
Control Technology Evaluation Using Methanol Fuel," SAE Paper
901112, Hellman, K. H. and G. K. Piotrowski, May 1990.
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-31-
14. "NOx Reduction Is Compatible With Fuel Economy
Through Toyota's Lean Combustion System," Kimbara, Y. K., et
al., SAE Paper 851210, October 1985.
15. "Development of Methanol Lean Burn System," Katoh,
K., Y. Imamura, and T. Inoue, SAE Paper 860247, February 1986.
16. "Recent Developments in Electrically Heated Metal
Monoliths," Whittenberger, W. A. and J. E. Kubsh, SAE Paper
900503, February 1990.
17. "Evaluation of Metallic and Electrically Heated
Metallic Catalysts on a Gasoline-Fueled Vehicle," Hurley, R.
G., et al., SAE Paper 900504, February 1990.
18. "Camet Electrically Heated Catalytic Converter,"
Sales Literature, Camet Company, 12000 Winrock Road, Hiram,
Ohio, 44234, February 1990.
19. Formaldehyde Measurement In Vehicle Exhaust at MVEL,
Memorandum, Gilkey, R. L., OAR/OMS/EOD, Ann Arbor, MI, 1981.
20. "Formaldehyde Sampling From Automobile Exhaust: A
Hardware Approach," Pidgeon, W., EPA/AA/TEB/88-01, July 1988.
21. "Sample Preparation Techniques For Evaluating
Methanol and Formaldehyde Emissions From Methanol-Fueled
Vehicles and Engines," Pidgeon, W. and M. Reed, EPA/AA/TEB/
88-02, September 1988.
22. "Proposed Regulations For Low-Emission Vehicles and
Clean Fuels," Staff Report, State of California Air Resources
Board, August 13, 1990.
23. "Evaluation of Toyota LCS-M Carina: Phase II,"
Piotrowski, G. K., EPA/AA/CTAB/87-09, December 1987.
24. Federal Register, Vol. 50, No. 126, p. 27179, July
1, 1985.
25. "The Mechanisms Leading to Increased Wear In
Methanol Fueled^I Engines," Ryan, T. W., et al. , SAE Paper
811200, October 1981.
26. "Lubrication Experience In Methanol-Fueled Engines
Under ShoYt-Trip Service Conditions," Chamberlin, W. B. and W.
C. Brandon, SAE Paper 831701, November 1983.
27. "The Effects of Lubricant Composition on SI Engine
Wear With Alcohol Fuels," Marbach, H. W., et al., SAE Paper
831702, November 1983.
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-32-
28. The FRAM/CODE Oil Analysis program," Sales
Literature, Allied Automotive Aftermarket Division, Allied
Signal, East Providence, RI, 1990.
29. "Methanol Engine Durability," Ernst, R. J., R. K.
Pefley, and F. J. Weins, SAE Paper 831704, November 1983.
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APPENDIX A
DESCRIPTION OF TOYOTA LCS-M TEST VEHICLE
The Durability Driving Schedule for light-duty vehicles
consists of 11 laps of a 3.7-mile course. The basic vehicle
speed for each lap is given below.
Table A-l
Basic Lap Speed
Durability Driving Schedule
Speed
(miles per hour)
1 40
2 30
3 40
4 40
5 35
6 30
7 35
8 45
9 35
10 55
11 70
Each of the first nine laps contain four steps with
15-second idle periods. These laps also contain five light
decelerations from base speed to 20 miles per hour followed by
light accelerations to the base speed. The tenth lap is run at
a constant speed of 55 miles per hour. The eleventh lap is
begun with wide-open throttle acceleration from stop to 70
miles per hour. A normal deceleration to idle followed by a
second wide-open throttle acceleration occurs at the midpoint
of. the lap.
n
Figure A-l below is a diagram of one lap of the Durability
Driving Schedule taken from 40 CFR, Chapter 1, Part 86,
Appendix ,IV.
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Figure A-l
Durability Driving Schedule Lap
[From 40 CFR, Chapter 1, Part 86, Appendix IV]
0.7
SlQE
THEN ACCELERATE
TO LAP SPEED
0 AND 3,7
MILES
3,3
2,9
/DECELERATE
TO 20 M.P.H.
THEN ACCELERATE
TO LAP SPEED
START-FINISH
STOP
THEN ACCELERATE
TO LAP SPEED
DECELERATE
TO 20 M.P.H.
THEN ACCELERATE
TO LAP SPEED
STOP
THEN ACCELERATE
TO LAP SPEED
DECELERATE
TO 20 M.P.H.
THEN ACCELERATE
TO LAP SPEED
DECELERATE
TO 20 M.P.H.
THEN ACCELERATE
TO LAP SPEED
1,3
2,6 \ DECELERATE
TO 20 M.P.H.
THEN ACCELERATE
JO LAP SPEED
2,2 STOP
THEN ACCELERATE
TO LAP SPEED
ALL STOPS ARE 15 SECONDS
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APPENDIX B
DESCRIPTION OF TOYOTA LCS-M TEST VEHICLE
Vehicle weight
Test weight
Transmission
Shift speed code
Fuel
Number of cylinders
Displacement
Camshaft
Compression ratio
Combustion chamber
Fuel Metering
Bore and Stroke
Ignition
Ignition timing
Fuel injectors
2015 Ibs
2250 Ibs
Manual, 5 speed
15-25-40-45 mph
Ml00 neat methanol
Four, in-line
97 cubic inches
Single, overhead camshaft
11.5, flat-head pistons
Wedge shape
Electronic port fuel injection
3.19 inches x 3.03 inches
Spark ignition; spark plugs
are ND W27ESR-U, gapped at .8
mm, torqued to 13 ft-lb.
With check connecter shorted,
ignition timing should be set
to 10°BTDC at idle. With
check connecter unshorted,
ignition timing advance should
be set to 15°BTDC at idle.
Idle speed is approximately
550-700 rpm.
Main and cold start fuel
injectors capable of high fuel
flow rates. The fuel injector
bodies have been nickel-
plated, and the adjusting
pipes are stainless steel.
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APPENDIX B (CONT'D)
DESCRIPTION OF TOYOTA LCS-M TEST VEHICLE
Fuel pump
Fuel tank
Fuel lines and filter
Catalytic converter
(stock)
In-tank electric fuel pump
with brushless motor to
prevent corrosion. The body
is nickel plated and its fuel
delivery flow rate capacity
has been increased.
Stainless steel construction;
capacity 14.5 gals.
The tube running from the fuel
tank to the fuel filter has
been nickel plated. The fuel
filter, located in the engine
compartment, has also been
nickel plated. The fuel
delivery rail has been plated
with nickel-phosphorus.
1-liter volume, Pt:Rh loaded,
close coupled to the exhaust
manifold.
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