Five Ways to Prepare for a Smog Inspection

When bringing in your vehicle for a smog inspection, even a seemingly minor detail can determine whether it passes or fails. Photo: Discount Smog Check Centers (2015)

A vehicle can fail a smog inspection for a variety of reasons, so it’s important to be prepared prior to your appointment. Here are five common issues to address:

1. Warm up your vehicle. Since a smog inspection requires a vehicle’s catalytic converter to be hot, a cool engine can result in an unwarranted test failure. That’s why it’s a good idea to drive your vehicle for at least 20 minutes before bringing it to a smog check facility. If you know your wait time will be more than 30 minutes, keep your engine running to make sure it stays warm.

2. Give your battery time to reset. On most modern vehicles, the onboard computer system takes a day or two to fully reset following a power outage. To avoid any issues with your smog check, allot a couple of days of drive time after jumping or replacing a dead battery.

3. Be upfront about “check engine” light issues. Even if it’s off during the inspection, if your “check engine” light has been on recently, your car’s computer memory will have stored the code, resulting in a failure to pass the inspection. In this case, it’s better to be upfront with the mechanic and save yourself the fee for a pointless pre-test.

4. Complete any temporary repairs. While electrical tape is properly suited to mend things like wiring, it should never be used to repair loose hoses or other engine components, as this can lead to automatic failure of the smog inspection’s visual portion.

5. Make sure aftermarket parts are labeled. Any aftermarket engine replacement parts should be labeled with a legal EO (Executive Order) number issued by the California Air Resources Board (CARB), which signifies the organization’s approval. While an unlabeled part may not constitute an automatic fail, your smog technician must be able to verify that the part meets CARB’s standards. Without a proper label, the technician will need to do some research to verify the part, making a simple process a lot more difficult.

In addition to these preparatory steps, check your registration to see whether you’ve been directed to a smog check station or a STAR Certified station. A regular smog check station can’t test a vehicle that’s required to go to a STAR Certified facility, so don’t waste your time by accidentally going to the wrong place.

To find a Diamond Certified company in your area that performs smog inspections, visit www.diamondcertified.info.