Reduce engine power???????

[Jay]

From there I would suspect a bad battery (or a bad cell within the battery screwing with the current) or bad ground connection somewhere. Someone else I know kept having electrical problems in their 08 SLT and a new battery fixed it.

Wish I could help you more.

 

[MItahoe]

I have had this happen to my 07 twice in the 4 years I have owned it. Both times it was the accelerator pedal sensor. I had to have the accelerator pedal replaced both times.

 

[hambne]

I have an 04 burban ans the same happened. disconnected and fixed it for a very short time and took i to a mecn who had one of the big high dollar machine. The computer said that I had a mis-compare between the pedal sensor and the TB sensor. Found out that I have a bare spot on the TB plug.

 

[OklabyGodhoma]

Yep the plugs can definiately be the cause. It was sounding like she was in "limp home mode". Check for any codes and address, but put the correct plugs in place and save the money for other things.