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Check engine light

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My check engine light comes on only when I am stopped at a red light. Then as soon as I push the gas pedal and drive it goes off again and doesn’t come back on until I stop. It also doesn’t happen every time I stop either. Any suggestions?

“Any suggestions?”

I suggest you read the code (or have the code read for you) and get back to us.

That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.

Are you sure it’s the “check engine” light, which is usually amber or yellow in color?

It sounds like you may be seeing the oil pressure light, which is red and has a symbol of an oil lamp on it. When you let the engine idle at a red light, the oil pressure drops because the engine is running slowly. If it drops too low, the red oil pressure light will come on. Then, when you hit the gas and drive away, the engine speeds up and oil pressure increases, and the oil pressure light goes off. Then you slow down and stop at another light, and the light comes on again…

Check the oil level. If it’s low, that’s one reason the oil pressure light will come on. If your oil is up to the “full” mark and the light still comes on, it could indicate engine problems like worn main bearings, or problems with the oil pump. First check your oil level, then take the car to a trusted local mechanic if the light keeps coming on.

Make and model?

Just to elaborate a bit, the CEL will go on when a fault has been detected. If the fault is no longer detected, the light may go out. But, the ECM stores the code in memory. Even if the light is out, a code is probably still stored in memory and can be read.

Agree with jesmed that could be oil light but also could be the battery light indicating a charging problem. Strange behavior for a check engine light.