Okay, trucks a 02 V6 Silvy, 5.3 is from 02 as well, PCM is from a 02 GMC. I changed the VIN, disabled VATS, and flashed a 5.3 tune into it, still no fire.... All 144 grounds are hooked up, crank sensor, cam sensor, etc.... I even took the fuse box from a 5.3 truck and swapped em and still nothing. Im a newb at tuning, so bare with me. This is getting really frustrating, and i dont know where to go from here. Any help is appreciated. Thanks, Eric.

 

Does it crank? spark? fuel pressure,...... all these are info we need to help ya out

 

Well dude I was trying to figure out the same thing I was playing around on my Hp tuners and what might be the security relearn, try going in under flash and try relink vats!

 

Yes, it cranks, no it does not have spark.

 

I did the relink VATS also. Still nothing..

 

Well I will tell you that you could have dealership load a tune and relink everything, when my truck was turbo charged. I went back to NA I had the dealership reload a 5.3 tune, I saved it on HP tuners before I put it back to stock and then when I put everything back I loaded the tune and it worked perfect I asked him at the time he said all he needed is a VIN# and about the same year with the motor you want to use, just look on autotrader for VIN's or the vehicle you got the engine from!