I swapped the engine on my 02 from a 4.8 to a 6.0 I put a different computer but the truck won't turn on all it does is crank I put my stock computer back on and the truck turns over and stays on can anyone let me know how I can fix this problem

 

did you do the security relearn procedure

 

No I just asked found out that's another step I gotta do thanks

 

??? so its a secret?