okay so my buddy has a 2005 f150 truck with a engine swap 6.2 harley engine in it no catalytic converters , the issue is between 45-65 when we try and gas it, seems like it holds back and it does a sputter like a popping sound, so that day we changed out the fuel filter, now usually a fuel filter leaks a little, but his right when we took it off shot out gas, replaced felt fine, did a fuel system cleaner, we checked for vacuum leaks, checked the egr it was fine, the mass air flow sensor was fine, throttle was good we cleaned up everything, we are stuck right now and dont know where else to look i need a little help thanks for any input

 

Did he swap the ECM with the engine?

 

purplehazeir he got the computer also and he had it tuned out to run good with the 6.2 we ran the code reader and only the o2 sensors came out since he has no cats

 

The ECM might still be seeing the O2 sensor. The sensor cannot just be removed. It has to be dealt with by software or a dummy load (O2 sensor delete) installed on the harness.