General Motors Progress Towards the Federal Research Objective Emission Levels

Six vehicles that have achieved the Federal research objective emission levels at low mileage are described. Two vehicles have completed 50,000 miles of durability below the .41/3.4/.41 g/mi levels. Two vehicles failed these emission levels by 10,000 miles. There is a loss in fuel economy of about 7% and the driveability ranged from non-commercial to borderline commercial. The ongoing program objectives are to reduce the sensitivity of these systems to emission deterioration and driveability defects and to reduce the fuel economy losses.