1999 ford expedition 4.6
If you have actual spark plug wires there are 2 coil packs one on each bank of the front of the engine, the other version is coil over plug in which every cylinder has its own individual coil thus no spark plug wires I believe your year 4.6 came both ways.
You have coil over plug setup, you need to retrieve the codes to better assist you. Dont change coils that arent failed.
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