Common Reasons “Check Engine Light” Goes On

October 15, 2022

Nobody ever likes to see their vehicle’s “check engine light” come on. This light has the potential to indicate to you a simple problem with the car or a drastic mechanical repair. Either way, there’s no need to panic. Take a look at these common reasons for a “check engine light” to come on. 

Check engine light | Pit Shop Auto Repair - Libertyville

Time to Replace Oxygen Sensor

Your vehicle is equipped with an oxygen sensor that ensures the engine is burning the correct amount of fuel, and is running at peak performance. If the oxygen sensor becomes faulty, it can lead to too much or too little oxygen being burned, and damage various engine parts. If your check engine light is caused by an old or faulty oxygen sensor, you can turn the light off by having the sensor replaced.

Loose or Faulty Gas Cap

Something simple, such as a loose or faulty gas cap, can cause your check engine light to illuminate. A loose gas cap throws off your vehicle’s emissions systems because fuel vapors will leak out of the gas tank. Luckily, this problem can be fixed by checking your gas cap. If it’s loose, tighten the cap and see if your check engine light turns off. If the gas cap is damaged, you can replace it for $5-$10.

Failing Catalytic Converter 

Catalytic converters convert carbon monoxide and other dangerous gasses into harmless compounds, therefore reducing your vehicle’s emissions. If it starts failing, your vehicle will let you know by illuminating the check engine light. While most catalytic converters last the entire lifetime of the car, sometimes they will go bad and need to be replaced. Only an experienced mechanic should replace your car’s catalytic converter.

Faulty Spark Plugs

Spark plugs are responsible for igniting the fuel in your vehicle’s engine and sealing the combustion chamber. They can last approximately 100,000 miles, and when they go bad, you’ll know. If you have a bad spark plug, not only will your check engine light come on, but you may also feel a jolting sensation when you try to accelerate your car. Luckily, replacing spark plugs is cheap. 

Time to Replace the Mass Airflow Sensor

The mass airflow sensor helps your car’s computer inject the proper amount of fuel into the engine, increasing performance and efficiency. If you don’t have your car’s air filters replaced regularly, it can cause the mass airflow sensor to start malfunctioning and provide incorrect information — leading to poor gas mileage, car stalling, and increased emissions. The only way to resolve this problem is by having an experienced mechanic replace your mass airflow sensor and regularly replace your vehicle’s air filters. 

Check Engine Light On? Bring your Car to Pit Shop Auto Repair

When your check engine light comes on, there’s no better place to bring your vehicle to than Pit Shop Auto Repair. As a leading auto shop in Lombard, IL, we’ve helped Illinois drivers identify the cause of their check engine light and fixed the problem for them in no time. Contact us today to see how we can help with your check engine light.

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