Ok guys my dad has an 08 2500, fully deleted and has a PPE hot plus 2 on it. Just drove it today didn’t make it a mile down the road and got the engine power reduced message, then didn’t make it out of the gas station parking lot and got it again. He said he started getting it the other week randomly and sometimes it would run fine. I’m fairly clueless on duramax so where should I start? Told him to take his programmer completely off on his way home tomorrow and I’d bring our computer from work and try and pull a code on it. Or should I begin somewhere else? Thanks!