Pray

iTrader: (7)

I tuned my 06' Silverado over a year or so ago and have never had to put it into 4W Low. When I finally did it went into Reduced Power Mode and gave me a "U0107 Lost Commo with Throttle Actuator Control Module". It only happens in low. AWD, 2WD, and 4WD High have no problem. I tried messing with the tune to no avail. What gives? Any one else run into this? I am using EFI Live. Any help would be great.

iregret

iTrader: (4)

I found this (on accident actually). It's sorta related.

TSB on Reduced Engine Power - Chevy SSR Forum

Try the wiggle test. LOL.

01WS6/tamu

iTrader: (36)

2 options to determine what's happening.

Flash it back to stone stock to determine if it is related to tune. That's where I would start first just to have a solid baseline to go from to eliminate all possibilities of a gremlin hiding in the tune.

Start the truck and grab the harness on the driverside where it runs from the valve cover to the power distribution center and shake and twist that section of the harness really wrench that sucker around. I have had a crap load of these trucks breaking wires inside the insulation in this drip loop area.

Repeat this same procedure on the wiring harness where it leads to from the injector harness to the throttle body.

Next take the beauty cover off and there is a ground fastened to the top of block on the back passenger side. Use a swivel 13 and a 6 inch extension and a flex head ratchet. Remove this ground wire and pull it up to inspect it where it is crimped to the ring terminal Ive had this wire break right at the crimp. tug on it lightly to see if the insulation stretches and it pulls in half.

ak2007r6

iTrader: (1)

Have used my 4x4 low a few times since my truck was tuned with HP Tuners to pull some people out of the ditch and have not noticed any problems. Hopefully it's just a loose connection or bad ground.

Pray

iTrader: (7)

Thanks for the advice guys. I will try all of it. It only happens when I hear the front locker engage. I will let you know what happens.