I have a 2003 5.3 with a LS2 intake and Vrx3 cam(226/228-.585/.588-114). The engine also has a POWER throttle body. It has been in another shop as VATS was already taken out. Im not sure what else may have been changed also, so I have no original baseline. Just what I pulled first go. Sitting key on eng off the scanner numbers look good and seem to be correct during cranking. I tried to start with original tune that was in ecm and also followed the idle tune guide I found on here. Neither will run. The car starts to fire then dies. Occasionally it will run for a few sec then die. I have also played with the advance and airflow trying to get lucky enough to get a baseline log. Any help is greatly appreciated. Attached is the tune it came in shop with and also the tune after following the idle how tos. Hopefully I'm missing something simple as I am still learning, as always.