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A 1990 Olds Cutlass Calais with GM's Quad-4 engine was outfitted with a Camet® EHC system and tested for FTP emission performance after 4000 road miles. EHC operation on this vehicle reduced NMHC and CO F17P emissions by 77% and 67%, respectively, versus the vehicle's stock catalyst configuration. Absolute NHMC and CO FTP emissions were below California's ULEV 50,000 mile standards with EHC operation. EHC heating strategy tests showed that a post-engine start heating schedule was nearly as effective as a pre-start heating schedule in reducing cold start hydrocarbon and CO emissions. Tests comparing vehicle and emission performance with different engine control parameters indicated no change in EHC effectiveness with respect to cold start emissions for the two calibrations evaluated here.

Two large, heavy light-duty gasoline vehicles (2004 model year Ford F-150 with a 5.4 liter V8 and GMC Yukon Denali with a 6.0 liter V8) were baselined for emission performance over the FTP driving cycle in their stock configurations. Advanced emission systems were designed for both vehicles employing advanced three-way catalysts, high cell density ceramic substrates, and advanced exhaust system components. These advanced emission systems were integrated on the test vehicles and characterized for low mileage emission performance on the FTP cycle using the vehicle's stock engine calibration and, in the case of the Denali, after modifying the vehicle's stock engine calibration for improved cold-start and hot-start emission performance.

The integration of advanced emission control technologies including advanced three-way catalysts and advanced, high cell density, ultra-thin wall substrates with advanced gasoline powertrains and advanced engine controls is necessary to achieve near-zero tailpipe emission requirements like California's SULEV or PZEV light-duty certification categories. The first gasoline vehicles meeting these near-zero regulations have been introduced in California in 2001. Advanced three-way catalysts targeted for these near-zero regulations feature layered architectures, thermally stable oxygen storage components and segregated precious metal impregnation strategies. Engine calibration strategies focused on tight stoichiometric air/fuel control and fast catalyst heat-up immediately after engine start are important enablers to achieve near-zero hydrocarbon and NOx emissions.

A 1991 Toyota Camry equipped with an electrically-heated catalyst (EHC) system was evaluated in duplicate over the Federal Test Procedure (FTP) with three different fuels. Evaluations were conducted with the EHC in place but without any external heating, and with the EHC operated with a post-crank heating strategy. The EHC system was placed immediately upstream of an original production catalyst, which was then moved to a location 40.6 cm from the exhaust manifold. The three test fuels were: 1) the Auto/Oil industry average gasoline, RF-A; 2) a fuel meeting California's Phase II gasoline specifications; and 3) a paraffinic test fuel. Non-methane organic gas (NMOG) emission rates with the EHC active were similiar with all three fuels, with absolute levels less than or equal to California's 50,000 mile Ultra-Low Emission Vehicle (ULEV) standard. Substantial differences, however were observed in the ozone forming potential of these fuels with the EHC active.

A 1991 Toyota Camry equipped with an electrically-heated catalyst/light-off converter system was evaluated for emissions in duplicate over the light-duty Federal Test Procedure (FTP) with three different fuels. Evaluations were conducted with the electrically heated catalyst (EHC) in place, both without any external heating and with the EHC operated using a post-crank heating strategy The EHC system was placed immediately upstream of an original production catalyst which was located 40.6 cm from the exhaust manifold. The three test fuels were: 1) a fuel meeting California's Phase II gasoline specifications; 2) a low-sulfur (48 ppm) version of the Auto/Oil industry average gasoline; and 3) the Auto/Oil industry average gasoline, RF-A. On average, NMOG emissions and the ozone forming potential of the exhaust hydrocarbons exhibited the following trend for tests run in unheated and EHC-active modes: Phase II < low-sulfur RF-A < RF-A.

The integration of advanced emission control technologies including advanced three-way catalysts and advanced, high cell density, ultra-thin wall substrates with advanced gasoline powertrains and advanced engine controls is necessary to achieve near-zero tailpipe emission requirements like California's SULEV or PZEV light-duty certification categories. The first gasoline vehicles meeting these near-zero regulations have been introduced in California in 2001. Advanced three-way catalysts targeted for these near-zero regulations feature layered architectures, thermally stable oxygen storage components, and segregated precious metal impregnation strategies. Engine calibration strategies focused on tight stoichiometric air/fuel control and fast catalyst heat-up immediately after engine start are important enablers to achieve near-zero hydrocarbon and NOx emissions.