What Do I Do When My Check Engine Light Comes On?

The last thing you need while you’re driving along is for your check engine light to come on. This is a sign there is something wrong with your vehicle that requires immediate attention. The only indication your car, truck, or SUV is in trouble could be the check engine light, so don’t laugh off the warning. Rather, pull into Demore’s Automotive and we’ll fix the problem for you. Here’s what could be wrong.

Catalytic Converter Failure

Your car, truck, or SUV’s catalytic converter is part of the exhaust system and it controls dangerous emissions. The catalytic converter takes the toxic gases and pollution-causing materials from your engine and converts them into less-toxic pollution by causing an oxidation and reduction action. If your catalytic converter is failing, your vehicle is releasing toxic pollution into the air.

Gas Cap Seal Failure

Have you ever noticed when you twist your gas cap off to fill your fuel tank it makes a hissing sound if the tank is empty? This is because your vehicle’s gas cap creates a seal once you twist it back on. If you were in a rush the last time you filled up and didn’t twist your gas cap on tight enough, it might not have sealed and this will cause the check engine light to come on.

Mass Airflow Sensor Trouble

A mixture of air and fuel is what starts your vehicle’s engine and keeps it running. For example, when you turn your ignition on, the spark plugs generate a spark to ignite the fuel and air mixture which is needed to create combustion. The mass airflow sensor measures and regulates the air coming into the engine to ensure the air/fuel mixture is optimal for engine performance.

Oxygen Sensor Issues

Your oxygen sensor checks the amount of unburned oxygen in your vehicle’s exhaust. Like the mass airflow sensor, the oxygen in the exhaust is measured to ensure your vehicle is using the right air/fuel mixture to run. The oxygen sensor does not have its own warning light, so your check engine light will light up on your dashboard if the oxygen sensor isn’t measuring the oxygen levels properly.

Spark Plugs

You might be seeing a theme at this point. All of these parts work together to keep your engine running efficiently and if your spark plugs are worn or you have trouble brewing with the spark plug wires, your check engine light might come on. It used to be you should have your spark plugs changed every 30,000 miles; now, some vehicles can go 100,000 miles before the change. Check your owner’s manual.

Demore’s Automotive in Palmer, MA can run an engine diagnostic test to find the reason why your check engine light came on and then fix it.

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