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Re: check engine light on

Is an ignition coil going bad if you see moisture on the exterior rubber that sits in recessed sparked plug well area. I noticed driving into work that the car hesitated a little (stumbled) when going 45 mph.

You can have moisture collected on the ignition system without a problem. Assuming this is just moisture from the air and not a coolant leak. The thing you need to make sure isn’t happening is the ignition pulses aren’t leaking out of the ignition wiring and going to the ground of the engine. If the ignition system is working like it should be all the spark will go to the plugs. If the hesitation problem keeps up you should have a shop check things over to look for the cause.

It’s not a sign of a bad coil, but moisture on the spark plug wires can cause misfiring if the wires are old.

How old are the spark plug wires on your car?

The moisture is probably just condensation, and should dry off as soon as the engine warms up.

Year, make, model, mileage would be helpful if you expect a helpful answer…