An Emissions Test Failure Can Be Caused By the Following Problems

Few things can be more frustrating than your vehicle failing its emissions test. It must pass the test in order to be registered. Mark’s Auto Service can find out why your vehicle failed the emissions test and repair the issue. Here are several common reasons why an automobile will be unable to pass the state-mandated emissions test.

Catalytic Converter Failure

If your catalytic converter is going bad, you might smell sulfur or rotten eggs and your vehicle will likely overheat. A bad catalytic converter cannot take carbon monoxide and convert it into carbon dioxide. Consequently, there will be too much carbon monoxide in your vehicle’s exhaust and your car will fail the emissions test.

Check Engine Light

If your check engine light is on, this is an instant test failure. It doesn’t matter if there is no reason behind the check engine warning. Even a malfunctioning engine control module that turns on the check engine light when everything is okay will result in an emissions test failure. The check engine light must be off in order for your vehicle to pass.

Electrical Problems

Electrical problems can cause the check engine light to come on for no reason. They can also cause the check engine light to come on because there is a problem with your vehicle’s electrical system. Usually, the check engine warning signals a problem with the system sensors or engine control module. This will result in an emissions failure.

Exhaust System Trouble

Naturally, if there is a problem with your vehicle’s exhaust system, it won’t pass the emissions test. Common problems in the system include clogs, leaks, or a failing mass airflow or oxygen sensor. You may also have engine performance issues if your exhaust system isn’t working properly, and your car will overheat if the exhaust manifold is leaking.

Fuel and/or Combustion Issues

Your engine needs just the right combination of air and fuel for proper combustion. If there is too little or too much fuel in the mixture, your vehicle will not pass the emissions test. For example, too much fuel in the mix will result in excess carbon gases being released through the vehicle’s exhaust, and this will definitely cause an emissions test failure.

Ignition and Detonation Concerns

Finally, the air and fuel mixture is pushed into your vehicle cylinders where the spark plugs ignite it. This is called detonation, and worn spark plugs cannot ignite the mixture properly. Consequently, there will be unburned gases that make their way from the combustion chamber to your vehicle’s exhaust, and this will cause your vehicle to fail the emissions test.

Stop by Mark’s Auto Service in Loves Park, Belvidere, Roscoe, and Rockford, IL, or Loves Park, IL, if your vehicle did not pass its emissions test. We will find the source of the problem and fix it.

Photo by welcomia via Canva Pro

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