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Q: Engine came back on after getting spark plugs and wires replaced.

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So a couple days a go my check engine light came on I took it to advance auto and they gave me a code of P0303 which is a cylinder 3 misfire. I took it to a mechanic to have it looked at turns out my spark plugs, wires, and coiler needed replacing. That was Thursday when they fixed that. Now my check engine light has come back on and I'm not sure why. Everything is tight and right where it should be so why is my check engine light back on??

My car has 165000 miles.
My car has an automatic transmission.

Hello. If there are no physical symptoms, it will probably be necessary to rescan the computer and pull the fault codes. A Check Engine Light can literally signal any of hundreds of possible problems. The codes will at least give you a starting point as to where to look for the problem. It could be related to the previous P0303 code or it may be something completely different. Have the codes read and then have a mechanic pinpoint the underlying cause of the Check Engine Light.

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