I just bought 2005 F350 2 months ago. Ran great til it had a bad hesitation and low power. Engine light then came on. Checked code--something about a misfire. Cleared the code, light was back on before I got back home from parts store. Took it to the dealer, they replaced the fuel pump under warranty, also replaced the fuel filter. Now the hesitation is back and light is back on. Truck has 8100 miles on it and all I've done is change oil and put a K&N filter in it. Anybody have the same problem? what was the fix?

 

Maybe try a new set of spark plugs.

 

Misfire to me means a bad coil or plug, but generally a bad coil pack. But with so little miles on it?

 

I've been struggling for over a month now with a similar problem. Tonight I think I got to the bottom of it - I replaced the spark plug cables, and the stutter went away. Since your car is new, your problem may not necessarily be related to wear (as it was in my case), but I would still replace the cables and the coil packs (in this order because of their price tags ...) This should be covered under warranty, so you may even not need to pay a thing ...

HTH ...

 

This car uses COP (coil on plug), so go to the specific clyinder. For example, a P030x means "misfire in clyinder x". And don't worry, this is a OBDII code, which means there are up to like 16 clyinders that could be missing. Once you locate the specific clyinder, then do a base compression check to make sure the compression is where it should be, then possibly check the fuel injector (it should be clicking rhymically, easily heard with a stethoscope). Take a look at the plug; How does it look? If soaked in gas, look at the injector to be stuck on. If coated w/oil, then go deep into the engine.