I have an 04 250 stock except for 4inch turbo back exhaust. the truck will not pull my 5th wheel at all. the truck will run fine by itself but put the trailer on and it spits and sputters at around 2100 RPM.
The FICM is new the EGR is new and the HPOP just got changed. What else could be going wrong?

 

Fueling problem.Have the pressure checked.

 

Ran around with pressure gauge and it read 55psi consistently.

 

Where did you install the gauge at?

Also, there is a "no power" troubleshooting thread in the Tech Folder that might help.

 

Not sure the Mech at the dealership installed it and we drove around with him and his laptop. If I give it full throtle it seems to be okay at least until today, after the HPOP was replaced. I will look into the thread you listed and see if comes close to my proplem. Ford Has had my truck every day for a week.