Automotive emissions of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) are major factors in metropolitan air pollution in the U.S. There are three major sources of exhaust emissions: test, off-cycle, and malfunction, i.e. emissions measured in the regulatory or certification tests, the excess caused by driving at higher power than in the tests, and the excess caused by malfunction of on-board emissions control systems (ECS), respectively. This report focuses on the two loopholes in the exhaust emissions control program: off-cycle and malfunction emissions. Malfunction emissions occur in modern cars because some models do not have robust ECS. This result supports criticism from other directions that inspection and maintenance (smog check) programs aimed at malfunction of individual vehicles are stop gap at best. In contrast, if new information technologies, such as remote sensing and on-board diagnostics, are developed and used to identify malfunction prone models and to motivate the design and manufacture of models with robust ECS, then substantial emissions reductions can be achieved before MY2010.

  • Supplemental Notes:
    • Sponsored by The Energy Foundation, Lawrence Berkeley Laboratory, Laboratory Directed Research and Development Program under a U.S. DOE contract and Oak Ridge National Laboratory, Lockheed Martin Energy Research under a U.S. DOT FHWA contract.
  • Corporate Authors:

    American Council for an Energy-Efficient Economy

    1001 Connecticut Avenue, N.W., Suite 801
    Washington, DC  United States  20036
  • Authors:
    • Ross, M
    • GOODWIN, R
    • Watkins, R
    • Wang, M Q
    • Wenzel, T
  • Publication Date: 1995-11


  • English

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 110 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00722151
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jun 17 1996 12:00AM