Amends the Clean Air Act to revise provisions for compliance with emissions standards by vehicles and engines in actual use.

Official title: A bill to amend the Clean Air Act to promote competitiveness in the motor vehicle aftermarket and to preserve consumer freedom of choice to select parts and service of the consumer's own choosing, and for other purposes.

Amends the Clean Air Act to revise provisions for compliance with emissions standards by vehicles and engines in actual use. Repeals a requirement that manufacturers warrant that new motor vehicles or engines are: (1) designed, built, and equipped so as to conform with emissions standards at the time of sale; and (2) free from defects in materials and workmanship which cause failure to conform for its useful life. Requires, instead, a production warranty that the vehicle or engine is equipped with emission control components designed to enable such vehicle or engine to conform at the time of sale with emissions standards for the first 12 months or first 12,000 miles. Repeals provisions for motor vehicle or engine parts certifications by manufacturers or rebuilders for compliance with emissions standards. Limits a free replacement obligation of manufacturers to emissions control components installed for the sole (currently, sole or primary) purpose of reducing, vehicle emissions. Limits specified performance warranties to: (1) the first 12 months or 12,000 miles; and (2) certain components installed for the sole purpose of emissions control. Revises provisions for manufacturers' instructions for the maintenance, replacement, and repair of emission control parts or components to eliminate requirements that: (1) such instructions correspond to regulations promulgated by the Administrator of the Environmental Protection Agency; and (2) replacement parts be certified. Eliminates provisions for waivers of a prohibition against such instructions, including conditions on the purchaser's using components or services unconnected with the manufacturer. Specifies that waivers of the prohibition against State or local standards for emissions control of new motor vehicles or engines subject to Federal standards will be given only: (1) insofar as numerical emission levels are concerned; and (2) if such standards and new motor vehicle certification and other tests are consistent with Federal standards. Specifies that tampering prohibitions refer to parts or components placed on or in motor vehicles or engines for the sole purpose of controlling emissions. Prohibits State new motor vehicle emission standards in nonattainment areas from including any provision similar to the production or performance warranty provisions under the Clean Air Act. Sets forth effective dates for specified amendments made by this Act.