I would like to get in on this conversation as well..... I got home, took gas cap off and no change. I turned off, unplugged MAF, restarted and idle went up and down a few times and steadied out at about 700 rpm, idled smooth but do have the service traction control across readout and traction control icon on dash. Turned off, plugged back in and back to rough idle. Service is still on. ??

 

Hi Hoff I did the same thing Sunday. With the same result. It actually seemed to run better.
Search for unplugging MAF sensor and diagnosis it was something that I didn't think to do
I had to unplug the battery to reset the service traction control
hummerz had a great though that was much appreciated.

 

Sorry, I thought every diy Hummer owner had a scanner with the ability to clear codes. Yes you will get a code, with any sensor disconnected, however you will need to clear codes after testing.
Btw, I use crc maf sensor cleaner.

 

Yes, I have a code reader. Didn’t need to clear anything. Let it sit all night, started this morning and no codes. If I leave the heat or air on in recirculate mode, runs fine but basically means my A/C is on all the time. If I could just get it to idle 50 more rpm’s the 3 would be smooth.