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Q: Blinking Check Engine Light, issues with rpm, possible spark plug issue?

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Recently, while I am driving, my check engine light will start blinking and my rpm will go up and down when it shouldn't. I've looked up some things and I keep getting results for misfiring cylinders and possible spark plugs issues. When it starts acting up, I usually smell somewhat of a gas smell, not sure if that's related.

My car has 160000 miles.
My car has an automatic transmission.

Hey there. The gas smell you experience is most likely due to the unburned fuel due to the engine misfiring. Since you smell unburned fuel, the cause is most likely spark-related. If any spark plug is not firing correctly, the spark plugs themselves can be at fault or they can be the effect.

If an ignition coil is not firing the spark plug, then the bad coil is the cause and the misfiring plug is the effect. Also, the ignition coil may not be firing properly due to the coil itself being shorted or possible receiving a poor signal from the engine control unit.

You should have a certified technician look into the Check Engine Light as soon as possible. Continued driving with the light flashing can cause internal engine damage if not corrected.

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