I've been having the same exact problem with my '07 burb, though it never shut off while driving until yesterday when of course my wife was driving. Needless to say I got a frantic phone call. Was relieved that it happened while she was pulling into a parking lot. It threw a P1516 code.
About a month before this happened the truck was making a rattling noise coming from the top of the engine. I couldn't pin point where it was at first. It sounded like something was loose and bouncing around in the intake manifold. For the most part it sounded a lot louder on cold startups. A few days later I finally found out what the noise was. I pulled off the air intake hose to the throttle body and saw the butterfly rattling violently. It would quite down a little when the truck warmed up. What was strange was that it would rattle like that for a few seconds when I turned the truck off and when I turned it to the on position. I also had hesitation when I stepped on the gas sometimes, as well as surging at highway speeds.
Checked the wires from the harness on the TB as far back as I could. Also checked the pins in the harness as well. All looked and felt ok. So today I decided to pull the TB off and clean it. It wasn't too dirty for having 94k on it, though I bought the truck with 90k so I don't know if the previous owner ever cleaned it. While I was at it I pulled off the cover on the TB where the harness plugs in just to check it out. The gears worked fine, though a little dusty and there were no teeth missing on them. The circuit board was inclosed so I couldn't look at that. The only other electrical connection I could see were 2 copper pins on the throttle body side that attached to the cover to another set of 2 pins via a metal coupling. When I first pulled the cover off one of the couplings came off one of the pins pretty easily. Not sure if that may have been the reason why the butterfly was chattering. I was able to secure it more tightly before I reattached it......Would have taken pics if I knew I was going this deeply into it. Seeing what I am talking about would make it a lot easier to understand......I was in a time crunch so I wasn't able to blow out all the dust and spray some electrical cleaner on the pins before I put it back together.
I let it sit for a few hours and tested to see if I would get the rattling again. So far so good. It was only 32* out so I'm going to let it sit overnight and check it in the morning to see how it is. In the next few days I'll pull it off again to blow out and clean the dust on the inside of the cover.
---------- Post added at 09:11 PM ---------- Previous post was at 09:08 PM ----------
My wife does not feel safe driving the Tahoe with this defect.
My wife said the same exact thing. She said until it is fixed then she will never drive it again.
