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Q: I'm having a problem with arcing from the plug wires.

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I'm having a problem with arcing from the spark plug wires and making the car run rough and stalling. I have replaced the plug wires, plugs, and ignition coils and it is still doing it. At night you can still see arcing coming all the way up the wires. I'm not sure if it is a bad motor ground somewhere. All the sensors have been replaced and fuel pump.

My car has 218000 miles.
My car has an automatic transmission.

The problem you are having is not due to the ignition system but is a result from an improper amount of fuel getting into the cylinders. If your engine is running lean, then it may cause the engine to not be able to spark across the spark plugs. A lean condition can be from poor fuel quality, excessive cleaners in the fuel, low pressure, dirty injectors, carbon build up on the valves, or engine vacuum leaks. You should have the computer data checked to see if the engine fuel controls are running the engine lean due to a vacuum leak or lack of fuel. Have the systems diagnosed by a mechanic to narrow the cause of the problem you are having. If you need help looking into this, YourMechanic offers a repair and diagnosis service preformed by a certified mechanic that will commute to your location to inspect why it’s running rough.

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