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My wife and I received her father's 2002 F150 4.2 5 speed 2 wheel drive truck after his passing. He purchased new plug wires and wanted to replace them. So, this weekend I put in new plugs, plug wires, changed the air filter, and changed the oil and filter. Started up and ran really rough. Threw my code reader on after taking it around the block and found the following codes...
P0316 Misfire detected in first 1000 revs, P0302 Cylinder 2 misfire, P0305 Cylinder 5 misfire, P0306 Cylinder 6 misfire. New plugs were Motorcraft plugs, but had skinnier center compared to the ones that came out of truck.
Where do I start? What do I do? I am really confused as I have changed plugs and wires before and always had vehicle run better or same as before change.
Assuming there was no trouble before, it appears you have the three cylinders plugged up wrong at the coils.
The system is a waited spark type.
The cylinders are paired 1-5, 2-6, 3-4 to each respective coil.
Good luck.
I'll have to check into that, but I did double check the coil and wire routing a couple times. And the truck was running fine before wire and plug change over. I should have left well enough alone. Father in law thought the change would be good.
Finally had time to check into this. I retraced the wires, and low and behold, 5 & 6 were switched. Not sure how it happened, but at the coil they were switched. I had written on the wires the numbers with a sharpie, and the 6 smudged a bit and I took it as a 5.... So.. Installer error.
Wires in correct order on coil and it runs great now. I feel much better, even telling my error
Makes it worse when the truck runs better and the wife asks what was the cause. And you have to tell her basicially it was a crossed wire and it was what she said to begin with.. Nah.. it is not that simple.. has to be something else....