What goes into emissions testing?

We all know that emissions testing (also sometimes called a Smog Check) is an essential part of being a car owner these days. The Environmental Protection Agency sets the basic emissions standards for all vehicles sold in the United States. While that's true, it's up to each state to maintain those standards. As a result, states often adopt even stricter rules, including California. Some states don't require emissions testing, though California requires them every two years. New residents are required to have a smog check done before they can register their vehicle in California. If for some reason, you do not pass your emissions test and your car is not exempt, you will not be able to drive your vehicle within the state legally.

Now, before getting into the requirements for the California emissions test, what does testing emissions even do? This test looks at your car's emission production to give an overview of its functional state. During an emissions testing, your vehicle is inspected for emissions both visually and functionally. Your auto mechanic will measure the amounts of various chemical gases that are released into the air when your car runs. The physical inspection looks at your car's exhaust system to see if there are potential ways to limit those emissions.

Depending on where you go for your emissions testing, there are three current forms of tests used in California. The two-speed idle test, the acceleration simulation mode test, and the on-board diagnostics test. The two-speed idle test measures emissions through the tailpipe while your car is idle, as well as at low and high speed. It's usually used on older vehicles, though location can also be a factor for its use. The acceleration simulation mode test is generally used on very old cars. It includes a drive-on dynamometer that can measure the exhaust emissions while being driven. In the last test, the on-board diagnostic test measures the data it receives from your car's computerized diagnostics system. Due to changes in automotive technology, this test only applies to vehicles made in 2000 or newer.

To get one of these emissions tests done, you should visit a STAR station, a testing location, or a testing and repair location. For those with cars that have higher levels of emissions, it may be a good idea to visit a STAR certified station. When you do visit these locations for an emissions test, make sure to bring your driver's license, proof of insurance, your vehicle's title, and registration.

Once you have the results, your emissions information is recorded and registered with the Bureau of Automotive Repair. This agency then determines if you have passed your emissions test. You'll receive a dated vehicle inspection report, as well as a receipt that says whether you passed or failed. This certificate is what you'll need to register or renew registration at the Department of Motor Vehicles.

For over 24 years, Autotrend Auto Repair Auto Repair has been providing the greater Campbell area with the best auto mechanics in the business. As time passes and automotive technology continues to evolve, you can count on our auto mechanics to be ahead of the curve on training and certification. For the best auto repair service and emissions testing, schedule an appointment online or give Autotrend Auto Repair a call. You'll be glad you did! Schedule an appointment for service or contact us online for a stress-free auto repair experience. See you soon!



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