How to Pass a Smog Check

  1. Research Center
  2. /
  3. How-To Research Articles
  4. /
  5. How to Pass a Smog Test
Man doing a emissions test
Show me your papers!
If you own a car, you've had the experience of going to get a smog check. It's funny that we call it a "smog check" when really, it is a check to see how clean the emissions are from your vehicle. Emissions testing determines the level of air pollution that is emitted from the exhaust of your car, truck or SUV. If your vehicle fails to pass the emissions test, you have to make repairs to the vehicle and then have it retested.
Every state's smog testing stations are different, but where I live, it always seems like I am crossing a border into Soviet Russia. Those stations are always painted grey and there are far too many signs telling me what to do for my liking. Grim attendants motion for you to move forward in tiny increments. You expect them to have German Shepherds at their heels. There are "double yellow lines" painted on the floor that I must stand behind. The attendants often appear to be sent from Central Casting, answering a call for "Grim Gulag Guards." They want to see my "papers." Then they insert an electronic cord which plugs into my car's brain. There's a lot of fiddling around with a computer screen before the operator fixes me with a grim look. At this point, the fluorescent lights overhead begin to blink and shudder in an unsettling manner. They should have one of those big rubber stamps for "PASS" or "FAIL." Maybe I'm reading too much into this experience.

Smog Check History

First, you may be wondering how we got here in the first place. Smog testing was introduced in the late 1970's as part of the Clean Air Act. The first Smog Check program in the United States was implemented in March 1984 (coincidence?) in California. It came about as a result of the passing of Bill SB33 in 1982. SB33 requires that any vehicle manufactured after 1976 must participate in the smog check program every two years. The aim of the program is to reduce air pollution from vehicles by ensuring that all cars with excessive emissions are repaired in accordance with federal and state guidelines. Today, 33 American states require smog check vehicle inspections to help control emissions.
The original smog check was looking for hydrocarbon and carbon monoxide gases. Over the years the program has evolved and become more sophisticated. In 2010 the Air Resource Board and the Bureau of Automotive repair sponsored legislation designed to improve the program to reduce air pollution through the use of new technologies. This took advantage of the on-board diagnostic (OBD-II) fault codes technology that has been installed on vehicles since 1996. The program eliminated tailpipe testing in favor of emissions monitoring systems.

What you've come here to learn is how to pass a Smog Check and find out what can cause your car to fail, not read an Orwellian novel such as "1984." So, what can you do to improve the odds that your vehicle will pass inspection? Let's find out. Naturally, you'll want to make sure your car is firing on all cylinders before you make your way to the gulag, er, Smog Check Station. A well-maintained car is more likely to pass. But if your vehicle isn't running its best, there are a few things you can do (besides bribing the station attendant) to improve your odds of passing.

Get Ready for your Smog Check

Until a smog certificate can be provided, car registration will not be renewed. If your vehicle fails a smog check, you have no choice but to complete repairs to your vehicle and then have it retested.As soon as your registration renewal notice comes in the mail calling for a smog check, prepare by having vehicle maintenance performed beforehand. Your car's owner's manual outlines required maintenance at specific mileage intervals. Be sure to perform regular oil and filter changes, tune-ups, and make sure your tires are properly inflated. Your local Lithia Auto dealer can handle all that for you. When you bring your car to a Lithia dealer for service, we'll do all of the above plus we'll check all the OBD-II diagnostic codes to make sure your vehicle is ready for its smog check. 

Smog me, baby!
Remember that the bottom line to pass a smog check is to have your vehicle meet the emission standards required in your state. Make sure your car is running right before you head down to the gulag, er, smog check station. Your Lithia Auto dealer can help with that. Find your local Lithia dealer here.