What the Check Engine Light Could Mean

October 15, 2022

When your car’s check engine light illuminates on the dashboard, it’s usually accompanied by a sinking feeling inside your stomach. The light could be a minor issue, but sometimes it’s indicating something serious. Although the only way to know for sure what caused the check engine light to come on is to bring it to an experienced mechanic. Here are some of the most common causes for you to consider.

Check engine light | Pit Shop Auto Repair - Lombard

Loose or Faulty Gas Cap

Sometimes the problem can be as simple as a loose gas cap. The lines and the valances in your gas tank system recirculate gasoline vapors and keep them from escaping. If the gas cap is loose, the system cannot circulate properly, and as a result, can cause the check engine light to come on. This can easily be resolved by getting a new gas cap.

Worn Spark Plugs

Your spark plugs ignite a mixture of fuel and air to create combustion and power for your engine’s cylinders. They’re what makes your engine able to operate. If they aren’t operating properly, it can cause an engine misfire, which can increase emissions and cause weaker performance of your engine. 

Dirty or Faulty Mass Airflow Sensor

The mass airflow sensor is responsible for measuring the amount of air that’s entering the engine. This is an important process because it determines how much fuel is needed to run the engine. When dirt and oil build up on this part, it can cause the check engine light to turn on. Sometimes you can clean it enough to turn the check engine light off. If that doesn’t work, you’ll need to have it replaced. 

Faulty Catalytic Converter

The catalytic converter is responsible for changing carbon monoxide into carbon dioxide, therefore protecting you and the environment. A faulty catalytic converter will reduce fuel economy and performance and increase your emissions. If your check engine light is caused by a faulty catalytic converter, you will need to replace the catalytic converter, and fix the original problem that caused the catalytic converter to go bad in the first place.

Malfunctioning Oxygen Sensor

Your vehicle’s oxygen sensor is responsible for measuring how much unburned oxygen is in the exhaust. It communicates with the vehicle’s electronic control unit (ECU) to help figure out what the right air-to-fuel ratio should be for the best engine performance. In addition to activating the check engine light, when the oxygen sensor malfunctions, it could also cause your vehicle to run irregularly, sound rough when it idles, and cause slow acceleration. 

Bring Your Car Into Pit Shop Auto Repair

When your check engine light comes on, there’s no better place to bring your vehicle than Pit Shop Auto Repair. We’ll identify the root cause of your check engine light, fix the problem, and have you back on the road in record time. Schedule an appointment now by calling us at (630) 812-0790, or click here to schedule an appointment online.

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