1. Make Sure Your Car Runs Properly – If your car is not running properly you should not get a smog check until you get it fixed. If you do not, then there are high chances that your vehicle will fail the smog check. Check with a mechanic first and get the necessary repairs done to ensure that your car will pass the smog test.
2. Warm Up Your Engine – It is recommended that you drive your vehicle for at least 20 minutes prior to arriving at the smog station. This will ensure your vehicle is properly warmed up and is running at it’s optimum level.
4. Keep Tires Inflated- The smog technician may will to drive your vehicle on a dynamometer as a part of the smog test process. Even and correct tire pressure will allow the vehicle to be driven with greater stability and accuracy during the smog exam. This will improve the overall emissions output of your vehicle by allowing the engine to maintain a constant and steady load. Correct and even tire pressure may be the deciding factor between a borderline vehicle failing or passing the smog test.
5. Change Oil – If it’s close to your next oil change interval, go ahead and do it before the smog check. The PCV (positive crank ventilation) system of your vehicle is designed to allow your engine to breath fumes located in oil compartments (oil pan, ect.). The fumes are then burned through the combustion process. If the oil in your engine is contaminated due to inadequate oil changes it may very well cause your vehicle to fail the inspection.
Contaminated oils are high in Hydrocarbons (HC) and will present a rich mixture to the engine chambers. Avoiding oil changes not only causes pre-mature engine wear but can also cause your vehicle to fail the smog inspection. Change the engine oil.
6. Check Engine Light Off – Make sure your vehicle’s Check Engine Light or Malfunction Indicator Lamp is not illuminated. A constantly illuminated Check Engine or MIL light is an automatic smog failure. A certified repair shop can diagnose the check engine light condition and offer you an evaluation and estimate.