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California STAR Directed Smog Inspections (STAR program)

The smog inspection program is a vehicle assessment check-up carried out to reduce air pollution. Vehicles with excess emissions are identified during the inspection. Depending on their condition, they either get repaired or retire. The STAR smog program has been efficient in the reduction of air pollution caused by cars. The inspection exercise is carried out by various smog stations that have been licensed by the California BAR.

What Type of Vehicles are Required to Undergo a Smog Check?

Vehicles that use alternative fuel, those powered by gasoline and hybrid ones manufactured from 1976, should undergo the assessment exercise in the following conditions.


  • The vehicles that are eight years old since the manufacturing year and newer do not need a biennial smog evaluation.

  • Those vehicles that are four years old since their year of manufacture and newer ones do not have to change their smog check ownership.

Add four or eight, respectively, to determine the year your vehicle will require change-of-ownership smog assessment or a biennial smog evaluation. For instance, a vehicle that was manufactured in 2018 will start undergoing Biennial evaluation in 2026. Additionally, the same car will have to change smog assessment ownership if it is sold in or after 2022.

Where can I get a Smog Check Near Me?


There are numerous STAR stations located in different towns in California that have been licensed by the government to conduct smog evaluation. Consequently, you do not need to travel to a different city or town to take your vehicle for smog assessment. For instance, if you are in Walnut Creek, you do not have to travel out of your city to seek the service. To find a station near you, google online for “smog check near me” and get numerous suggestions.


Alternatively, you can visit the California BAR website and fill in your location details and get directions. When filling in the information, you should include the correct data so that you can be directed to a STAR office near you. For instance, if you come from Contra Costa County, fill in Walnut Creek on the city field if you are located on the east of San Francisco Bay area.


As you visit the smog check station, you should carry your DMV registration renewal notice. It will assist in making sure that the correct information is sent to DMV electronically. The BAR does not regulate assessment tests or repair fees. Various STAR stations charge different amounts.

What Can I do to Ensure My Vehicle Passes a Smog Inspection


You are likely to pass the inspection if you do not tamper with the vehicle’s emission-control equipment. Moreover, maintaining your car as per the owner’s manual increases the chances of passing the test. Furthermore, in case the vehicle has an engine problem, ensure it is repaired before visiting the STAR station. More importantly, do not ignore a flash or blink that indicates a malfunction in the vehicle.

If you are not sure whether your car will pass the test, you can opt for a prior unofficial test. The pre-inspection test is provided before undertaking the official assessment test. However, it is an optional test that may be charged by the authorized consumer.

The steps of a Smog Inspection

The test takes approximately twenty to thirty minutes. It is designed to check the type and amount of pollutants emitted by a vehicle. The inspection may include conducting any of the following tests.

  • Tailpipe emissions inspections

  • Checking the functionality of the vehicle’s OBD system

  • Visually inspecting the emission control system and components

  • Inspection of the vehicle’s ignition timing, evaporative fuel system, engine light, gas cap, and gas recirculation system.

What to Do if a Vehicle Fails a Smog Check

After the inspection, the STAR station will issue the Vehicle Inspection Report. If your vehicle fails an evaluation test, the reasons that caused the failure will be indicated in the report. If you do not understand the results, you should ask for clarification from the STAR office. In case you still need to use the vehicle that has failed the assessment, you should have it repaired. The repair should be carried out by a station that has been licensed by the California state to conduct smog inspections repair. If the STAR station you had visited is licensed to conduct both assessment and repairs, you can have your car repaired at the same station. On the other hand, if it is only permitted to conduct an assessment, you will have to look for a station that is credited to conduct Smog assessment repair.


After completing the repair, your vehicle should be retested. If it passes, you will be provided with a final report, and a certificate will be sent electronically to DMV. In case there are any issues during the assessment procedure, and you do not agree with the results, you can set an appointment with the state referee and get assistance.

California has Programs to Assist Vehicles that Fail the Smog Evaluation Test


If your vehicle fails the test, the state can assist you through the Consumer Assistance program. The program offers a repair or retirement option. For repair aid, the state offers financial help to income-eligible consumers. However, the repair will have to be conducted in a STAR station that is under a state contract to perform the service.


On the other hand, vehicle retirement aid is eligible if you can receive an incentive and opt to retire the vehicle instead of repairing it. If you take this option, the vehicle should be retired at a dismantler that is approved by the state.

The Gross Polluter Vehicle


 50% of smog produced in California is from motor vehicles. GP represents ten to fifteen percent of these vehicles. They are the vehicles that have been recognized by the smog evaluation program as the major source of smog emissions. If a vehicle is in this category, it has to be tested in a STAR smog center for clearance. Vehicles that are not classified in the GP category do not have to visit a STAR certified station. They can be cleared in any local station.

Stations Allowed by the State of CA to Carry Out the Smog Program


Smog assessment stations can be licensed to function as any of the following.

  • STAR Test-only: they can carry out inspections on vehicles, but they cannot repair them.

  • STAR Test-and-Repair: they are certified by the state to conduct both smog inspection and repair.

  • Non-STAR certified Test-Only station: they can inspect the vehicles that have not been classified in the GP category and those that have not been specifically directed to a STAR station.

  • Non-STAR certified Test-and-Repair: they can assess, repair, and certify vehicles that were not classified as GP in their last evaluation and those not directed to STAR stations.

  • Repair only: they are stations that only credited to perform repairs. They cannot conduct Smog evaluation, and also they are not qualified for the STAR program.

To know the kind of station you need to take your car, check your DMV registration renewal form. It has been indicated whether your car requires to be evaluated in a STAR station or a local Smog inspection station.


Smog inspection is a requirement of the State of California if your car model is within the set years. The inspection should be carried out in a STAR station or a local station, depending on the instructions in your DMV registration renewal form. The smog certificate proves that a vehicle has passed the inspection. The main aim of the inspection is to reduce air pollution, which is harmful to human health.

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