EXHAUST AND EVAPORATIVE EMISSIONS FROM A BRAZILIAN CHEVROLET FUELED WITH ETHANOL-GASOLINE BLENDS

Abstract

Exhaust and evaporative emissions from a 1974 Brazilian Chevrolet Opala were measured using gasoline and various ethanol-gasoline mixtures. For this car, which was designed to operate with rich air-fuel mixtures, additions of up to 20 percent ethanol to gasoline reduced exhaust hydrocarbon and carbon monoxide emissions, but increased exhaust aldehyde and nitrogen oxide emissions. The leaning of the air-fuel mixture, due to ethanol addition, was the primary cause of the exhaust emission changes. Evaporative emissions were slightly higher with 10 percent ethanol in gasoline, than with gasoline alone.