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Q: Check Engine light P0304.

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I am getting a Check Engine light code P0304. I've already had all the spark plugs replaced and coil number 5.

A: The code P0304 points to a misfire on cylin...

The code P0304 points to a misfire on cylinder number 4. Ford also has a funny cylinder identification pattern, different from many makes, and a diagram should be consulted to determine which cylinder is the right one. The spark plugs have been changed, now suspect the coil on cylinder number 4 or its wiring. A mechanic, like the ones here at YourMechanic, would be more than happy to assist you with an inspection on this engine misfire.

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