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5 Common Reasons the Check Engine Light Came On

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The check engine light isn’t always a welcomed surprise, but it is a helpful indicator that it’s time for your vehicle to have preventative maintenance. In a few cases, the check engine light may be alerting you to a simple fix. Its ambiguity can be frustrating and leave you panicked. To help bring more clarity to the check engine light, we have listed five common reasons the check engine light has come on. 

Spark plugs
Spark plugs send the needed spark to ignite the combustion process. While it would be nice if spark plugs last forever, they do wear over time. Work spark plugs will need to be replaced. If neglected, faulty spark plugs can cause a reduction in gas mileage and an engine misfire. 

Oxygen Sensor
The oxygen sensor measures how much-unburned oxygen is in the exhaust. This measurement is vital because too much or too little oxygen can damage your vehicle. If the oxygen sensor is damaged, the check engine light will come on. You may even notice black smoke coming from the exhaust and a rotten egg smell.   

Gas Cap
In some cases, there may not be a significant problem at all. If you recently got gas, you may not have securely fastened the gas cap. The gas cap prevents gas vapors from seeping out your vehicle and prevents fuel fires. If the gas cap is broken, you can purchase a new one at an automotive store relatively cheap.   

Catalytic Converter
If you’re noticing a sluggish engine performance, dark exhaust smoke, and a sulfur smell coming from your engine, the catalytic converter may have gone bad. This should be inspected right away before major engine damage occurs. The catalytic converter can be an expensive repair, and ignoring this can create a costlier problem. 

Mass Air Flow Sensor
A very particular amount of oxygen needs to mix with the fuel to start your vehicle properly. The mass airflow sensor measures the amount of air entering the engine to complete the combustion process. If the mass airflow sensor fails, your vehicle’s computer will alert you through the check engine light.  

Vehicle inspection and diagnosis in Brockton, MA

If your check engine light has come on, Green Auto Plus is here to help. Our team can run a comprehensive diagnostic test to determine the issue accurately. Our expert technicians are skilled in the latest automotive technology and are passionate about providing top-quality honest repairs. The check engine light doesn’t have to be ignored; we are currently offering a free check engine light scan and automotive advice. More diagnostics may be needed, but this will bring you one step closer to resolving the issue and safely getting your vehicle back on the road. 

Click here for more information

Or do not hesitate to reach out to one of our friendly service advisors for more information at 508-436-4495. 

Or shoot us a text at 617-843-5050. 

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