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check engine light

What Does My Check Engine Light Mean? And Some Ways to Fix It

Remember your first car and how the check engine light was always on? On modern vehicles the check engine light actually means something, but it still doesn’t tell you exactly what’s going wrong.  So you’re asking yourself, “What does my check engine light mean?”

You’ll need to go to a mechanic to have them scan your car to get the code that identifies the issue or even get your own code scanner. There can be hundreds, even thousands, of potential problems in a modern vehicle, but there are a few common problems that are often the cause of the check engine light coming on.

The Gas Cap

This one is simple and very easily fixable: if you see the check engine light come on stop and check that your gas cap is on, and if it is, then whether it’s fully tightened.

Cool Off

This is another easy one to diagnose and it’s not difficult to fix yourself, but it can potentially be a serious issue. If you haven’t changed your coolant recently your engine’s temperature will increase to the point where it can become dangerous. You’ll be able to see if the temperature is too high on the thermostat on your dashboard.

Bright Sparks

You’ll probably need a mechanic to diagnose this problem, but it’s easy and relatively cheap for them to fix. The spark plugs that ignite the air and fuel mixture in your engine’s combustion chamber can wear out over time, causing your engine to begin to fail.

Catalytic Converter

Without regular maintenance, the catalytic converter that turns poisonous carbon monoxide into less poisonous carbon dioxide can rust. Your vehicle’s sensors will let you know if this is happening, in which case you should take your vehicle to a mechanic as soon as possible.


The most common reason for a check engine light to be on is the oxygen sensor being triggered. A sensor in your exhaust checks the amount of oxygen leaving your engine and adjusts the oxygen levels to maintain efficiency. If the sensor fails then your engine won’t be able to operate efficiently and your fuel economy will suffer.

So, as you can see the check engine light comes on for some pretty serious reasons, and it also comes on for problems that you can solve by buying a bottle of coolant or screwing on the gas cap. So if you’re asking yourself, “what does my check engine light mean,” and none of this has worked unsure then ask a mechanic or even contact us– diagnosing it will only take a second and could reveal a serious problem.