how to replace #4 cylinder coil?
Literally 1 screw and an electrical connection.
4.6 engine or 5.4 engine?
5.4 is coil on plug. As Andrew stated above...remove electrical connection at the coil, remove small bolt and pull the coil off of the sparkplug. I would recommend only using Ford Motorcraft coils as the aftermarket ones sometimes don't last very long. Ford Motorcraft costs more, but in the long run worth it.
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