This report consolidates results from a number of emission testing programs on in-use passenger cars. Vehicles from the 1975 through 1981 model years were involved. The purpose of this effort was to examine the effect of 'high mileage' on levels of exhaust emissions. The emission levels from the vehicles involved were examined from four basic views: (1) 'As received' results of the top 15% (by odometer) versus similar results from the bottom 15% and 85%; (2) 'as received' results of vehicles with over 50,000 miles versus those with under 50,000; (3) the effects of restorative maintenance on high mileage vehicles; and (4) the effects of catalyst replacement on high mileage vehicles. The results show that the high mileage vehicles exhibit higher average HC and CO emissions than the lower mileage vehicles. The higher emission levels appear to be due to an increased rate of maladjustments, disablements and defective parts. It was also found that on the average, catalytic converters remain active beyond a vehicle's statutory 'useful life' of 50,000 miles and that restorative maintenance is an effective method to reduce average emission levels. Even further reductions were possible, especially in HC, through replacement of the catalytic unit.
Exhaust Emissions from High-Mileage Catalyst-Equipped Passenger Cars
1981
15 pages
Report
No indication
English
Characterization of Exhaust Emissions from High Mileage Catalyst-Equipped Automobiles
SAE Technical Papers | 1982
|Characterization of exhaust emissions from high mileage catalyst-equipped automobiles
Automotive engineering | 1982
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