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2005 Ford F-150 Question: Missing



nashta, 4.2L V6, Potwin, KS, January 05, 2014, 05:47

What causes it to miss at driving speed but, not at idle?

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  • Answer #1

    pushrod January 05, 2014, 06:31

    Defective coil pack or plug wires most likely. Yes the coli pack can cause a misfire and still run the engine! Scanner can test cylinder contribution to find the misfiring cylinder(s).

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