Hi i am on my second tune first being afm on 15 suburban which went good. Now i swapped 5.3 into my jeep out of 03 trailblazer. it is stock with different intake pipe no cam all parts of of good running truck. I made tune with out VATS and delete rear o2s because i have no cats. it starts and runs then dies 5 seconds in if it gets warm it will catch before it dies and revs up and then in 5 sec die again. i checked amazon harness had to repin MAF all seems good. Tried to make tunes to fix it still dies. Loaded factory VATS off tune same thing. Install my buddys ECM that is tuned for cammed engine that runs great. Tried copying what i saw different no change. Not sure what to do at yhis point any help would be great.