hey all, I have been searching the threads and trying a few things but to no avail nothing has worked. I will give a rundown of it. I have an 08 yukon xl denali 6.2. truck has been running fine other than a flickering headlight and gauge lights which I was told was my alternator. it tested good but was not working right I guess. anyway I was at store sunday and truck was running great as usual, but i started the truck and pulled out of parking space and thats where it all went south. stabiltrak, abs lights came on along with park assist off and gauges were going nuts. truck would not shift out of low 1st either and door locks were going nuts. I pulled into advance auto parts and proceeded to do a few things I have read about. I added a ground, not to battery from alternator but to wherre ground strap attatches beside brake booster. I took apart all grounds I could find and cleaned and greased them along with the main 175amp fuse and connections. also replaced my alternator and belt.
Nothing helped but sitting still and in park truck ran like a champ but gauges were still jumping everywhere. I noticed towards the end when I shut off truck and removed the key the truck stayed running for 5 min then shut off. I got truck towed home and was having it towed to mechanic the next day after 300 spent to no avail and when I went out the truck started and all was fine. but once it got to shop and they worked for 2 days they cant find where problem is and only have guesses. I am at a loss here.
Nothing helped but sitting still and in park truck ran like a champ but gauges were still jumping everywhere. I noticed towards the end when I shut off truck and removed the key the truck stayed running for 5 min then shut off. I got truck towed home and was having it towed to mechanic the next day after 300 spent to no avail and when I went out the truck started and all was fine. but once it got to shop and they worked for 2 days they cant find where problem is and only have guesses. I am at a loss here.
