Skip to main content

If you own a vehicle, you’ve probably heard about smog checks and how they are necessary to maintain air quality and reduce pollution. Smog checks are required by law in many states, including California, and failure to comply can result in fines or even the suspension of your vehicle registration. But what exactly happens during a smog check inspection?

During a smog check, a licensed technician will inspect your vehicle’s emissions system to ensure that it meets the state’s emissions standards. The inspection includes a series of tests and evaluations that are designed to identify any issues or malfunctions that could cause your vehicle to emit excessive pollutants.

The inspection process may vary slightly depending on the type of vehicle you own and the specific requirements of your state. In California, for example, there are two different types of smog checks: the standard smog check and the STAR smog check. The STAR smog check is a more comprehensive inspection that is required for certain vehicles or in certain geographic areas with higher levels of pollution.

During a standard smog check, the technician will begin by checking the “readiness” of your vehicle’s onboard diagnostic (OBD) system. This system is responsible for monitoring the performance of your vehicle’s emissions system and will generate error codes if any issues are detected. If your OBD system shows that all monitors are “ready,” meaning that all the necessary tests have been completed, the technician will proceed with the inspection.

The technician will then perform a visual inspection of your vehicle’s emissions system, looking for any obvious signs of damage or wear. They will also check for the presence of certain emissions control components, such as catalytic converters and evaporative emissions systems, and make sure that they are properly installed and functioning.

Next, the technician will connect your vehicle to a diagnostic machine that will measure the emissions output and perform a series of tests, such as the idle test and the acceleration simulation test. The technician will monitor the readings from the machine to ensure that your vehicle is within the allowable emissions limits.

If any issues are detected during the inspection, the technician will provide you with a list of recommended repairs. In some cases, the repairs may be minor and can be performed on the spot. In other cases, more extensive repairs may be necessary, and you will need to have the repairs completed before your vehicle can pass the smog check.

In conclusion, a smog check is an important part of vehicle maintenance that helps to ensure that your vehicle is running cleanly and not emitting excessive pollutants into the air. By understanding what happens during a smog check inspection, you can be better prepared to keep your vehicle in compliance with emissions regulations and avoid costly fines or registration suspensions.