Q: Misfiring after replacing plugs and coils in 05 F150

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After replacing the plugs and coils for maintenance, the truck misfires and doesn't idle correctly. We replaced all 8 plugs with motocrafts and all 8 powerpack coils. Truck ran perfect before the replacement but now won't idle and shakes horribly. Help me please.

My car has 125000 miles.
My car has an automatic transmission.

I would recommend starting with re-checking all of the plug wires to be sure they are properly connected. Misfiring and shaking may indicate that one or ore of them may not be firing due to an improper connection. If this does not solve the problem, you may also want to pull the spark plugs out to be sure they are properly gapped. In incorrect spark plug gap may also cause a misfire due to an irregular flash as it fires.

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