I/M Short Tests and Cutpoints for 1981 and Newer Emission Control Technology 851185
Manufacturers have used a number of alternative emission control technologies to meet the emission standards for 1981 and later model years. Each technology type can have malperformances that lead to high emissions, but the ability of inspection/maintenance short tests to identify high emitters varies considerably by technology. In this study, the relationships between malperformance types, FTP emissions and short test emissions were identified for several major technology types, using data from the EPA Emission Factor data base. Based on these relationships, methods to enhance the effectiveness of I/M tests are suggested. The analysis indicated that the most important factor governing the ability of any I/M short test is the presence of absence of secondary air. The short tests were found to be incapable of recognizing any malperformance except severe misfire if secondary air was present. Without secondary air, the short tests could identify many common malperformances leading to high emissions.
Citation: Duleep, K., Wang, D., and Crawford, R., "I/M Short Tests and Cutpoints for 1981 and Newer Emission Control Technology," SAE Technical Paper 851185, 1985, https://doi.org/10.4271/851185. Download Citation
Author(s):
K. G. Duleep, Dennis Wang, Robert Crawford
Affiliated:
Energy and Environmental Analysis, Inc., Arlington, VA
Pages: 16
Event:
SAE Government Industry Meeting and Exposition
ISSN:
0148-7191
e-ISSN:
2688-3627
Related Topics:
Emissions control
Environmental regulations and standards
Emissions
Environmental protection
Suppliers
Inspections
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