limp mode

OK guys this one has me stumped. I'm working with an ASDT bin file for a 1989 5.7 Camaro with a 1227165_6e xdf. Everything was going good, car was running pretty decent. Finally good enough I felt comfortable enough to take it out to get a datalog. I let the car sit overnight, got up this morning and started the car and let it warm up a little bit. Shut the car down to go inside to get my drivers license and when I tried to start the car again it went straight into limp mode. If I upload the stock AUM file to the autoprom it does not go into limp mode. I just cant figure out why it ran so good then 5 minutes later it goes straight to limp mode.