Understanding Your Car’s Emissions Warranty

Car's EmissionsThe Clean Air Act of 1970, as amended in 1990, called for vast changes to the law including an extended warranty of sorts. This little known provision of the law extends the warranty period to 8 years and 80,000 miles, which has the potential to same consumers money on big ticket replacement parts like the catalytic converter. If you suspect an emissions problem on your vehicle and are faced with a large repair bill, the following information could reduce your costs.

Performance warranty – No big deal here since coverage falls within the car maker’s three year and 36,000 mile new car warranty. As long as your vehicle has failed a state or local mandated emissions test during its first 24,000 miles or two years, your car is covered for the parts and labor charges needed to correct the condition. You must maintain the vehicle according to the manufacturer’s specifications and return it to one their dealers.

Design and defect warranty – For 1995 and newer vehicles “specified major emission control components are covered for the first 8 years or 80,000 miles.” As defined in the law these parts include: the catalytic converter, the electronic emissions control unit or computer (ECU) and the onboard emissions diagnostic device or computer (OBD). Often the diagnostic function is present in the ECU and does not require a separate device. Configurations can differ by car maker.

Exceptions – The type of vehicle that you own may affect the warranty since the time and mileage requirements are different for motorcycles, recreational vehicles and heavy duty trucks. Parts which are covered under the Performance Warranty that have a recommended replacement interval which is less than 24,000 miles are warranted only until the first replacement point. For example, a PCV valve which is changed every 15,000 miles would not be covered after its first replacement. Also, you must maintain your vehicle as prescribed in the owner’s manual and parts damaged due to accident or abuse are not warranted.

Owner’s manual – As usual this little book plays an important role in this process. Check it to find a complete list of covered parts that are specific to your make and model and to get guidance on how to file a claim under either of these warranties. More importantly, follow the recommended service schedule so you don’t jeopardize your 80,000 mile and eight year warranty.

Appeal process – If the dealer turns down your request for coverage under either warranty the EPA says you need to do the following:

  1. Get an explicit explanation in writing for the denial of your claim; and
  2. Obtain the name of the person at the dealership or manufacturer’s zone office who was responsible for the decision; and
  3. Ask for the name of the person at the manufacturer’s zone office to whom you should address your appeal; and
  4. Submit the appeal to the designated person and pursue it until you are confident that you have exhausted the process; and
  5. If you are still dissatisfied with the decision, write to the EPA at

U.S. Environmental Protection Agency

Office of Transportation and Air Quality

Light-Duty Vehicle Group

Attn. Warranty Complaints

2000 Traverwood Drive

Ann Arbor, MI 18105


Source: EPA, Warranties for 1995 and Newer Cars and Trucks