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Cars and Light Trucks

Inspection & Maintenance (I/M)

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Search the Document Index System (DIS) database to find:

  • Advisory Circulars
  • Applications for Certification
  • Certificates of Conformity
  • Certificate Summary Information Reports
  • Manufacturer Guidance Letters
  • Verify System Documentation

Best Practices

Vehicle inspection and maintenance programs (I/M) help improve air quality by identifying high-emitting vehicles in need of repair (through visual inspection, emissions testing, and/or the downloading of fault codes from a vehicle's onboard computer) and causing them to be fixed as a prerequisite to vehicle registration within a given non-attainment area.  The 1990 Amendments to the Clean Air Act made I/M mandatory for several areas across the country, based upon various criteria, such as air quality classification, population, and/or geographic location.

Regulations Policy Guidance
On-board Diagnostics Technical Guidance & Test Procedures
Tampering and Warranty State Status
Remote Testing Program Evaluations
Archive: Older Files & Publications

Contact:  Dave Sosnowski at 734-214-4823 or sosnowski.dave@epa.gov

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