Guys, can you give me some input here, I've read and done everything the forum says as far as deleting vats all the key immobilizers with all the emissions stuff. Here's what I have gen4 5.3 799 heads 224/232 581/581 @112 cam shorty headers 09+ map sensor 09+4l65e 17 pin internal p/n safety switch 07 e38/t42 09+PSI standalone harness. My gut feeling is it has something to do with the updated map sensor but I've referenced it to a 09 5.3/4l60 230/230 cammed truck for map quantities. I'm over looking something. Attached the tune files ,58 tune 3.hpt58 stock tune.hptdillon elliots compare file.hpt