Things That Cause the Check Engine Light to Come On

There are many things that can cause a check engine light to come on. Advanced Automotive advises that the reason why is simple: The check engine light is a catch-all. It turns on when the problem does not have a dashboard warning light of its own. A 2019 study demonstrated that the check engine light is very effective in reporting engine problems. The most common reasons why check engine lights come on are listed below.

Bad Mass Airflow (MAF) Sensor

A malfunctioning MAF sensor will cause the check engine light to turn on because it reports an error code when it malfunctions. You may also notice problems with your engine’s performance, such as stuttering or surging, and black exhaust smoke coming out of your tailpipe.

Bad Oxygen (O2) Sensor

One of the most common reasons why drivers end up with check engine warnings is failing oxygen sensors. The O2 sensor has a lifespan of about 60,000 miles to 100,000 miles. If your car has more mileage than that in the check engine light comes on, it could be a bad O2 sensor.

Catalytic Converter Malfunction

The catalytic converter can get clogged or malfunction after about 100,000 miles. A bad O2 sensor can also cause the catalytic converter to get clogged. Not only will you get a check engine warning, but you may also smell rotten eggs in your vehicle’s exhaust or coming from the engine.

Electrical System Trouble

Electrical system trouble, such as a malfunctioning engine control unit or system sensors can cause the check engine light to come on. In fact, if your engine control unit goes bad, your vehicle may shut down completely.

Fuel System Trouble

Fuel system problems can also make the check engine light come on. The issue could be something as simple as a loose gas, or something as complex as a dying fuel pump. Check your gas If your check engine light comes on as you are leaving the service station.

Spark Plugs Misfiring

Old and worn spark plugs can misfire and this will cause the check engine light to turn on. A problem with the engine control unit can also make the spark plugs misfire. Issues with the spark plug wires will also give you a check engine light warning.

Transmission Trouble

The transmission does not have a light of its own, so the check engine light will illuminate if it is having problems. You may also notice that your vehicle is having difficulty going into gear or shifting gears.

Vacuum Leaks

Finally, vacuum leaks can also generate the check engine warning. This is because the vacuum pressure leaking out of the vacuum hoses introduces too much air into your automobile’s engine.

Advanced Automotive in Stanwood, WA, can get to the bottom of your check engine warning quickly. Call us today to schedule an appointment.

Photo by BDoty from Getty Images SIgnature via Canva Pro

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