Emissions from three diesel cars using two fuel formulations were assessed. The three diesel cars included a prototype naturally-aspirated Fiat 131, a prototype turbocharged Fiat 131, and a 1981 Oldsmobile Cutlass Supreme. Each Fiat was tested with and without a prototype catalytic trap. Vehicle operating procedures used for test purposes included the 1981 Federal Test Procedures as well as the Highway Fuel Economy Test, the New York City Cycle, and an 85 km/hr steady-state cruise. Both regulated and unregulated gaseous and particulate emissions were measured. Organic solubles in particulate were analyzed for various constituents and characteristics including fractionation by relative polarity, benzo(a)pyrene (BaP), and mutagenic activity by Ames bioassay. Application of the catalytic trap oxidizer system to the Fiat prototypes resulted in significant reductions of organic and carbon monoxide emissions under all transient driving conditions examined. Total particulate emissions were reduced an average of 55 percent with the turbocharged engine and 65 percent with the naturally-aspirated engine. The Ames assay mutagenic response (revertants/microgram) of the particulate phase organics was elevated by the catalytic exhaust aftertreatment device, however the emission rates (revertants/km) were reduced an average of 66 percent with the turbocharged and 73 percent with the naturally-aspirated engines.

Includes bibliographical references. Cover title. "PB85-126126." "EPA-600/3-84-108." "November 1984." "Contract No. 68-02-2703." "Project Officer Ronald L. Bradow."

Emissions from three diesel cars using two fuel formulations were assessed. The three diesel cars included a prototype naturally-aspirated Fiat 131, a prototype turbocharged Fiat 131, and a 1981 Oldsmobile Cutlass Supreme. Each Fiat was tested with and without a prototype catalytic trap. Vehicle operating procedures used for test purposes included the 1981 Federal Test Procedures as well as the Highway Fuel Economy Test, the New York City Cycle, and an 85 km/hr steady-state cruise. Both regulated and unregulated gaseous and particulate emissions were measured. Organic solubles in particulate were analyzed for various constituents and characteristics including fractionation by relative polarity, benzo(a)pyrene (BaP), and mutagenic activity by Ames Bioassay. Application of the catalytic trap oxidizer system to the Fiat prototypes resulted in significant reductions of organic and carbon monoxide emissions under all transient driving conditions examined. Total particulate emissions were reduced an average of 55 percent with the turbocharged engine and 65 percent with the naturally-aspirated engine. The Ames assay mutagenic response (revertants/mg) of the particulate phase organics was elevated by the catalytic exhaust aftertreatment device, however the emission rates (revertants/km) were reduced an average of 66 percent with the turbocharged and 73 percent with the naturally-aspirated engines.