72-17
EXHAUST EMISSIONS FROM THE AUTO-MATE
RESEARCH CHEVROLET
March 1972
Thomas C. Austin
Test and Evaluation Branch
Mobile Source Pollution Control Program
Environmental Protection Agency
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Background
The Test and Evaluation Branch of EPA's Motor Vehicle Emission
Laboratory received several requests from Auto-Mate Research
Corporation of Fairmont, Minnesota, to conduct an evaluation of
their modified 1969 Chevrolet Kingswood. The vehicle had
received a brief 7-mode test previously at EPA's old Willow
Run facility. Results of that test did not indicate significant
reductions in emissions from levels that are typical of standard
1969 Chevrolets. Auto-Mate personnel claimed to have improved
the system and accumulated test data from an EPA approved
laboratory which indicated substantial reductions in emission
levels. A series of baseline tests and tests with the Auto-
Mate devices used was scheduled and performed in our Ann Arbor
laboratory.
Vehicle 5 Devices Tested
The vehicle tested w.as a 1969 Chevrole.t Kingswood station wagon
equipped with a 350 CID, four barrel V-8 and an automatic trans-
mission.
Several devices were evaluated. The first device was an air
bleed valve which caused an enleanment of the mixture during
light load conditions.
A "fuel valve" was installed between the fuel pump and the
carburetor. The Auto-Mate people apparently believed that at
light engine loads (loxv fuel consumption) the fuel pump pressure
forced the bowl inlet valve open and over-fueled the engine.
The "fuel valve" continuously by-passed a portion of fuel pump
discharge to the inlet side of the.. fuel pump.
An electronic device attached to the fender of the vehicle was
claimed to eliminate oxides of nitrogen emissions. A voltage
was supplied to the device and air was drawn through it by
intake manifold vacuum.
Two Auto-Mate Research fuel additives received a brief evaluation,
Both additives were claimed to eliminate oxides of nitrogen
emissions.
Test Program
Both the 1972 and the 1975 Federal Test Procedures were used.
These tests involve starting a vehicle that has been parked
in a 68-86°F ambient for at least 12 hours and operating it on
a chassis dynamometer simulating an urban drive. Vehicle exhaust
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is diluted to a constant volume and. a portion of the dilute
exhaust is collected continuously in sample bags. The con-
centrations of pollutants in the sample bags are then measured.
A flame ionization detector (FID) is used to determine unburned
hydrocarbon (HC) concentration. Non-dispersive infrared (NDIR)
analyzers are used for carbon monoxide (CO) and carbon dioxide
(C02)- A chemiluminescent analyzer is used to determine both
nitric oxide (NO) and nitrogen dioxide (N02). The sum of NO
and N02 is reported as NOx. Pollutant concentrations are used
to calculate the mass of emission per mile of operation, grams
per mile (gpm).
The two procedures differ in that the 1975 procedure is longer
than the 1972 procedure and it involves shutting off the
vehicle for 10 minutes and then restarting it and completing
the test. Weighting factors are applied to the hot and cold
starts in the 1975 procedure. Fuel consumptions were determined
using both weight and carbon balance techniques.
The most extensive evaluation was made on the combination of
the air bleed and fuel valve device. Three baseline tests of
the vehicle without the devices operational and four tests of
the vehicle with both devices in use .were run using the 1972
and 1975 procedures.
One afternoon was devoted to running steady state tests to
check the effectiveness of the two fuel additives and the
electronic NOx device. These tests were considered adequate
since the effectiveness of the additives and devices was
advertised to be immediate and significant.
Test Results
The test results are summarized in Tables 1, 2 and 3. Table 1
Gompar.e-S bas_eline test results to results obtained with the
fuel valve and air bleed operaħional- u-si-ng the 1975 procedure.
The vehicle with devices demonstrated a 33% reduction in unburned
hydrocarbons, a 541 decrease in carbon monoxide and a 7% increase
in oxides of nitrogen. Fuel consumption was determined by weight
of fuel consumed during the test and remained unchanged.
Table 2 is the same as Table 1 except that the 1972 test pro-
cedure was used. The vehicle demonstrated a 31% reduction
in unburned hydrocarbons, a 41% reduction in carbon monoxide
and an 8% increase in oxides of nitrogen with the air bleed and
fuel valve operational.
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Table 3 illustrates the results of the steady state testing.
Configuration 1 establishes a "baseline" for the additive
and NOx device tests. Results from configuration 2 demonstrated
no significant change in emission levels with the NOx device on.
Results from configurations 3 and 4 indicate increases in
hydrocarbons and carbon monoxide when the fuel additives were
used. There was no significant change in NOx levels. Con-
figuration 5 resulted in significant increases in carbon monoxide
and significant reductions in oxides of nitrogen when the fuel
valve was closed.
Summary and Conclusions
The reductions in hydrocarbons and carbon monoxide and the
increases in oxides of nitrogen observed during the test of the
air bleed and fuel valve are typical of devices that cause an
enleanment of the mixture. Steady state results comparing
configurations 4 and 5 indicate that the fuel valve also had
an enleanment effect on the mixture. The bubbles in the return
line coming from the fuel valve suggest that leaks in the
system were causing air to be entrained in the fuel.
Similar effects to those observed in the air bleed and fuel
valve tests can be obtained without add-on devices by altering
the idle mixture, jetting and power valving in the carburetor.
Many late model vehicles already have carburetors recalibrated
for lean operation at light loads. The use of enleanment
devices on these vehicles could cause stumble, surging and
missing. Hydrocarbom emission levels could rise drastically.
The steady state tests indicated that the fuel additives
and the electronic NOx device had no beneficial effects on
emissions. It appeared that the NOx device was an ozone (Oj)
generator. Ozone could react with nitric oxide to form nitrogen
dioxide. The NOx detector.used, however, was designed to
measure both NO and N02 as they are both hazardous pollutants.
Any ozone in the exhaust of the vehicle would also be un-
desireable.
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Table 1
Auto-Mate Research Vehicle
1975-76 Federal Test Procedure
HC CO NOx MPG
Baseline (no
devices installed)
Avg. of 3 tests 5.34 65.06 3,59 11.68
With air bleed
and fuel valve
Avg. of 4 tests 3.56 30.25 3.85 11.66
1975 Federal
Standards .41 3.40 3.0
1976 Federal
Standards .41 3.40 .40
Table 2
Auto-Mate Research Vehicle
1972-74 Federal Test Procedure
H£ GO NOx
Baseline
Avg. of 3 tests 6.12 86.54 3.51
With air bleed
and fuel valve
Avg. of 4 tests. 4.19 50.88 3.80
1972 Federal
Standards 3.4 39.0
1973-74 Federal
Standards 3.4 39.0 3.0
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Table -3
Auto-Mate Research Vehicle
50 mph Steady State
Configuration HC CO COz NOx
1
2
3
4
5
. Indolene 30 fuel ,
no air bleed, fuel
valve open, NOx
device off
. Same as 1 \vith
NOx device on
.Same as 2 plus #1
additive in fuel
.Same as 2 plus #2
additive in fuel
.Same as 4 with
fuel valve closed
1
1
1
1
1
. 2 7 gpm
.16
.51
.33
.36
3
4
5
5
8
. 84 gpm
.05
.51
.58
.34
496 gpm
466
459
464
441
3
3
3
3
3
.88
.75
.75
.58
.10
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