The following is only a partial representation of FAQs. For additional information regarding the smog check program, please refer to or you may access the complete Smog Check FAQ in pdf format here:Bureau of Automotive Repair.

The smog check program is the State's attempt to improve the quality of air we breathe. Basically, the smog check program is designed to identify and repair or remove vehicles with high emissions.
Your vehicle must be tested every other year (biennial basis). A smog check is also required when you sell your vehicle and it is more than 4 model years old. Some vehicles may require a Smog Check at a Test-Only or STAR Certified smog station.
Just as the name implies, a Test-Only smog check station is licensed to perform smog tests and nothing more. If your vehicle fails a smog inspection at a Test-Only station, state law will not allow them to perform repairs.
STAR Certified smog stations are licensed Smog Check stations that have met and uphold rigorous performance standards as established by the BAR. STAR Certified stations perform smog checks and repairs at the same location - facilitating the process for the consumer. STAR smog stations may also repair vehicles qualifying for financial assistance under the Consumer Assistance Program (CAP).
A financial assistance program available to consumers meeting certain income requirements and whose vehicle has failed a biennial smog inspection. Qualifying individuals may receive up to $500 toward the cost of repairs. There is a $20 co-payment.
The cost of repairing your vehicle to restore it to operable condition, may exceed the value of the vehicle. You may chose to retire your vehicle from operation with a dismantler who is contracted with the BAR and receive up to $1,000 for the vehicle.
CAP applications, as well as additional information regarding the smog check program may be obtained at
Federal, state, county, city, and special district agencies that own or lease passenger vehicles or light duty trucks are subject to the provisions of the Smog Check Program.
OBD II is self-diagnostic equipment that is incorporated into your vehicle's on-board computer and monitors all aspects of emission system's performance. When a malfunction occurs the "Check Engine" or "Service Engine Soon" message is displayed on the vehicle's instrument panel. The OBD II also stores information that can be retrieved and analyzed by qualified technicians utilizing OBD II capable scan tools.
Concerns may be voiced by contacting the Department of Consumer Affairs at (916) 952-5210.

Smog Exemptions

One of the most common questions received is, "How do I know if my vehicle is exempt from smog checks?"

Gas-powered vehicles 1976 model year and newer require a smog check with the following exceptions:

  • Gas-powered vehicles 6 model years or newer are exempt from the Biennial Smog Check inspections.
  • Gas-powered vehicles 4 model years or newer are exempt from the Change of Ownership Smog Check Inspection requirement.

Diesel-Powered vehicles 1998 model year and newer, 14,000lbs GVWR or less are subject to the Smog Check program beginning January 1, 2010.

  • The gas-powered vehicle exceptions above do not apply to diesel-powered vehicles.

Other exemptions include the following:

  • Two cylinder vehicles
  • Electric vehicles
  • Two-cycle powered vehicles, not including rotary engines
  • Motorcycles
  • Off-Highway vehicles

For additional information regarding smog check exemptions, as well as a handy chart in pdf format, please go to the Bureau of Automotive Repair website.

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