A buddy of mine's 6.4 wont start now.. He just put a new edge programmer and a dpf delete exhaust on it. Programmer a few days ago and exhaust today.. Said it ran good until he got home, shut it off and now it wont even crank over.. What are possible issues and things he should try? Said at first it threw some codes but none now.. Hes tried putting it to stock and even unplugging the battery and nothing . said he looked somewhere and it said he needed to put the dpf back on and plug a sensor back in and jump the starter. Does that sound right?