I have a 2000 v10 F250 4x4. 130,000 miles on it. Had huge problem with plugs spitting out on both banks. fixed three times. Transmission just went out last week. Lots of problems.
I love my truck other wise it would be in the bone yard. So I thought it needed a fresh drive train. I just installed a 01 v10 engine and trans with 50k miles, replaced cracked exhaust manifold with headers, always use synthetic fluids. I used my old intake with old injectors, all new ford plat. plugs (torqued with compound), all new C.O.P's. Old harness and brain. Replaced O2 sensors.
Ran scanner on it com up with misfire #5, so replaced coil pack on #5 reset codes, still misfire on #5. Engine shudders when load on it in low rpm's. ANY IDEA'S??????
The only thing I can think of would be bad connecter to cop #5. EGR? IAC?

 

Unfortunately it's #5, but I'd pull the spark plug and take a gander at it. After that swap COP unit with one another cylinder and see if the trouble follows it. Check for damaged pins in the COP and injector plugs for that cylinder also. While you have the plug pulled you can also do a quick compression test to rule out any mechanical issues. If the trouble stays with that cylinder, it can't be too many things causing it.

 

Ok I will try that now. Thank you

 

You could also use a spare spark plug, put it in the end of the COP while it's plugged into the harness, and ground the plug. Then start the motor and make sure you have a spark there. If not, it would have to be the harness if the COP is OK (swap with another one is a good idea).

Also, try disconnecting the fuel injector and see if it runs any differently.

 

Ok replaced the coil pack with a known good pack for the fourth time. used test light on connecter end check out ok. (noid light) also checked out fuel injecter for #5 cylinder checked ok with noid light. suprisingly with injecter disconnected engine still runs smooth at idle. Right now all codes are clear but usually will act up after about an hour driving. will check back later. Thanks for your help.

 

Do a compression check ... especially on that one cylinder.

 

I will try that. Of course #5 is the hardest to get to.. Thanks.

 

you could have a bad injector that got a small piece of dirt in it. .do you know how long the motor sat in the bone yard? good chance is drive it a few hundred miles and see if that cylinder comes around, could have been that a valve in that cyl. sat open and has formed some rust or junk on it and needs a short time to reseat.
i see it a lot on marine motors improperly stored over the winter here. when they don't seal up the intake and exhaust properly.