Why Your Car Might Fail Its Smog Check | Brookfield, WI | Silver Lake Auto & Tire Centers
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3 Common Reasons Cars Fail Emissions Tests

Take Care of These Repairs First!

Are you wondering what you need to do to prepare for your vehicle’s next emissions test in Brookfield, Wisconsin? The good news for diligent vehicle owners is that it should be very easy for your vehicle to pass when you’ve kept up with its maintenance needs. Some common reasons that vehicles fail could be easily identified and fixed prior to testing with routine maintenance service. Silver Lake Auto & Tire Centers want our drivers to complete their emissions tests with confidence and as little stress as possible. That’s why we’re sharing these common reasons that cars fail smog checks, so you can avoid them! See if your vehicle needs these repairs before your next inspection!

  1. Faulty Oxygen Sensor
  2. Oxygen sensors are routinely cleaned and replaced during tune-ups to ensure they accurately measure the amount of unburned oxygen that’s released in the exhaust. Unfortunately, they wear out easily and it’s not an uncommon repair item. A faulty sensor that hasn’t been replaced will cause your vehicle to fail its emissions test, so it’s best to take care of it ahead of time.

  3. Rich Fuel Mixture
  4. If you’re told that your vehicle is “running rich,” that means there’s too much fuel in the fuel to air mixture. This could be caused by an old air filter, failing oxygen sensor, leaking injector, or by excessive fuel pressure.

  5. Ignition System Problems
  6. The ignition system must be functioning properly and well-maintained to pass a smog check. If not, the test may detect hydrocarbons and result in failure. Defective ignition systems are caused by worn-out spark plugs or a distributor cap.

  7. EVAP Failure
  8. The Evaporative Emissions Control System (EVAP) stops gasoline vapors from being released into the atmosphere. Leaks in vacuum hoses, vents, valves, and/or gas caps may cause damage to this system.

Does your vehicle need one of these repairs before its next smog check? Ask the professionals at Silver Lake Auto & Tire Center in Brookfield, Wisconsin for assistance! We’re here to simplify your testing process and make sure your vehicle is fit to pass the first time!

Written by Dan Garlock