If your state or local government mandates car smog checks, you already know the fear of your vehicle failing. It could mean some pricey repairs just to keep the car compliant and licensed for the road. Taking some precautions will go a long way, and we have simple tips on how to pass.
Identify the culprits.
Though we always advocate for regular maintenance, there are some items easily overlooked. If you know of a drivability issue, fix the car before your smog check so you at least don’t lose your test fee just to hear what you already know. Once that’s done, ask your smog test place if they will perform a pre-inspection. Results do not get reported and the fee is generally less, plus you will have more details on what’s likely to cause a fail on the test.
Change your oil and top off other fluids.
When oil in the engine becomes well-used, it can let off more emissions. An oil change and topping off of other fluids (including the gas tank) will also increase operating efficiency.
Try fuel additive.
Before you fill your gas tank, add a well-known brand designed to get carbon deposits inside your engine. Forget about automotive snake oils that made wild promises. Though it alone may not tip the scales in your favor, you will have a more efficient running engine.
Warm it up.
A smog check on a cold engine can appear much different than the same engine after warm-up. The catalytic converter needs time to heat and effectively reduce tailpipe emissions. Try to get in some 20- to 30-minute drives in the days before the emissions test and on the day itself.
Check your tires.
Confirm all four of your tires’ cold pressure readings are even and at recommended inflation. If your car undergoes a dynamometer test, increased rolling resistance from under-inflated tires will do no favors.
Fix the check engine light.
One light, so many reasons, from catastrophic malfunction to loose gas cap. For you or your shop, there could be sleuthing with a scan tool to identify the malfunction codes causing the check engine light’s frequent appearances, but that means time saved from guessing.