New to the forums and I need some help, I recently installed a remanned long block in my 91 f150, installed it a month ago and have been fighting it since firing it up, lacks power off idle, seems to idle fine and runs fine as long as I drive it like I stole it but if the pedal aint matted it bucks and chugs and runs like ****, I have changed everything and cant get it right ive about had it at this point. I have new injectors,new iac,new tps, new 02 sensor, plugs/wires/cap/rotor, new fuel filter,new fpr, no vac leaks that I can find im about to jerk the engine back out of it pull wheels n tires lift n shocks and send it to the crusher and buy a new truck. only code its popping is no movement on the egr but its got egr delete so that makes sense and that's it. This weekend I plan on pullin the upper back off it pullin the valve covers and checking torque on the rockers but I have no idea where to go from here any input would be greatly appreciated. Oh yea its a speed density truck and I swapped the sensor with one I had removed from my fox body mustang that didn't help either.

 

What engine? If the 5.0 did you get the wrong year with the different firing order?