How to Pass the California Smog Check

Unless your car is electric or newer than six years old, you most likely need a smog check every two years to drive legally in California. Taking your car in for this test can be nerve-wracking, but it isn’t all up to fate. You can increase the likelihood of passing your next smog check by following these tips.

DIAGNOSE THE CHECK ENGINE LIGHT

If the check engine light comes on, you must have the problem fixed to avoid an automatic smog check failure. A quick trip to a car repair shop will reveal what’s wrong. The solution may be as simple as tightening the gas cap, or you may need to replace the spark plugs, mass airflow sensor, or catalytic converter.

WAIT A BIT AFTER DISCONNECTING THE BATTERY

If you recently jump-started or replaced your car battery, wait at least one week before going in for a California smog check. When a car’s battery dies or is disconnected, the computer resets, erasing the internal emission monitors required to pass a smog test. You’ll be good to go once you drive 100 to 200 miles with the new battery.

GET AN OIL CHANGE AND TUNE-UP

Dirty oil can trigger a failed smog test, so it’s wise first to get an oil change. While your car is in the shop, ask the mechanic to visually inspect the engine for any cracked, broken, or loose hoses that could contribute to higher emissions. Be aware that most mechanics disconnect the battery during a tune-up, so you’ll need to drive those 100 to 200 miles before taking in your car for a smog check.

TOP OFF THE COOLANT AND GAS

A smog check may involve running the engine at high speeds while the vehicle is stationary. To prevent vapor from getting into the fuel line and throwing off the test results, go in with a full tank of gas and a topped-off coolant system.

DRIVE ON THE FREEWAY

The catalytic converter is an engine part that converts harmful pollutants into less harmful emissions. It must get hot to do its job most effectively, so it’s helpful to frequently drive on the freeway for one to two weeks leading up to your smog check. This burns out any residual oil and gas from the exhaust system for the cleanest emissions possible at test time.

GET A PRE-INSPECTION

If you’re not confident your car will pass a smog test, consider requesting a pre-inspection. This puts your car through its paces without recording the results with the DMV. If you schedule your pre-inspection far enough out, you’ll have plenty of time to fix any problems before your registration expires.

All Tune and Lube offer STAR certified smog tests in La Habra, CA. We’re also here to help if you failed a recent check. Our smog repairs will resolve your concerns and get your car in compliance with California emissions standards. Call us today at 714-871-4144 to learn more, or request an estimate online.