Rjsena29

I took my 05 f150 into the dealership to get my spark plugs changed along with all the drivetrain fluids flushed, new serpentine belt, and fuel filter. The truck ran fine when I brought it in. Got it back and all of a sudden I was driving, and check engine light starts flashing, and the temperature gauge read that I was overheating, but it really never did overheat, and the truck also began to run rough while all this was happening. I took it back to the dealership they scanned it and said the #1 cylinder was misfiring. Of course they said it had nothing to do with the work that they did on it. They told me it could be a problem with the valve, but they weren't sure, they told me it had to be further diagnosed for an additional cost, of course. I took it to an independent mechanic, and he came to the conclusion that it was the coil, so he replaced it. Low and behold I drove it on the highway, and really got on the gas, and the same symptoms occurred only now it's not intermittent it's constant, and my engine is running really rough. Does anyone have any insight on what might be wrong?

nrivera04

Replace the spark plug for gee whizzes... it's possible they broke it during the install. Don't forget to torque it down to 28 ft lbs.

Mastercraft1981SnS

What engine do you have in your truck? As @nrivera04 said they could have broken one when they installed it.
I would think its very possble of breaking because the torque specof 28ft lbs is high for a spark plug. In my line of work most plug torque spec are around 15ft lbs. Its also very easy to over torques something.

Rjsena29

The independent mechanic did say he checked the plug, and it was fine, which is why he ended up changing out the coil and boot. I'm wondering if you guys are right, maybe I should just replace the spark plug. The good thing is it's the #1 cylinder-should be easy enough to swap out real quick. I'm guessing since the plug was new, and was just previously taken out, it should come out without having spray any carb cleaner down in there.

techrep

iTrader: (1)

Also after replacement of the plug check the connections to the fuel injector and COP.