I'm working on an '04 Blazer, 6 cyl, with this same issue. My bosses rig. (I'm a MOPAR guy)

It has been to 1 mechanic 3 times and he keeps replacing the accelerator pedal.
It just got back from a dealership where 6 different mechanics looked at it and none of them could pinpoint the problem. They want to charge him $800 to replace the TPS (witch is part of the throttle body on this model. How stupid is that?!), and will NOT guaranty this will fix the problem. ???????????
So much for Mr. Goodwrench! A ASE certified, Goodwrench trained, 5 star dealer can't fix their own cars?!?!?
Do they NOT know about this site??
This was the first place I looked!

I'm going out to do the wiggle the wire thing and inspect the harness.
I hope that's it, I'm gonna charge him $800!!!! WITH a guaranty!

Thanks shawnvw,
EZ1

 

Where is the throttle body under the hood? I have the same issue on a 2003 Z71 Tahoe and I quess I need to check the wiring and/or replace the Throttle possitioning sensor? right?

Thanks for any advice.

 

JUst bought a used 03 Yukon and was wondering what is Chevrolet's position on this. At 65-70 mph on the interstate and the vehicle goes to reduced power with traffic bearing down from behind, is that not a serious safety issue?

 

H!
All you have to do is check/replace the wiring near the throttle body. DO NOT CHANGE anything expensive(throttle body, pedal positioning). Cost me 140.00$ and problem never occured again (it has been 9 months). GM should recall these as it is indeed very dangerous. My Silverado got stuck in a mountain area with a 25ft fifthwheel attached. Scared the hell out of me.

 

I'm going to say, Chevrolet doesn't give a rats behind!
They clearly know this is an issue with some models.
Their best mechanics can't nail down exactly was causes it, or what exactly fixes it.

For some, the fan clutch cures the problem, others it's the bad crimp at the TPS plug.
For me, it took a fan clutch, replacement of the TPS wires and three accelerator peddles to fix the problem. The last peddle was a factory. The first and second after market ones didn't fix it.


I'll compare this to the 3800 V6, where in a stroke of Chevy wisdom, they decided to run coolant through the plastic intake plenum.
After a few years, the plastic can't handle the heat cycles.
A hairline crack develops just inside past the throttle body and gives the impression of a blown head gasket. (coolant in the cylinder)
What did Chevrolet do for the unfortunate saps that bought one of these car?!? NADA, ZIP, So Sorry.
You can still find these cars on Craig's List for cheap. Dry it out, replace the plenum, and sell it.
But, the plenums are getting harder to find in the junk yards.
I've flipped a dozen of these cars for a good profit because of this design flaw.


EZ1

 

Dorman makes a complete kit for $199 comes with plenum , all gaskets and injector o-ring. The real cause of the problem is the EGR pipe under plenum is too close to intake. Dorman kit has a smaller diameter pipe to replace old one which fixes the problem for ever.

As far as the oe post. You need to wiggle the wire to the t-body and see if reduced power light comes on, if not you need a new t-body.

 

Hey guys. Today when I got off work I slammed the accelerator and this reduced engine power light came on, on my 2007 trailblazer ss and then the engine lost all power. So I pulled over and turned truck off the waited about ten seconds. The restarted truck and worked fine. But every time I tried to accelerate fast it would repeat the same incident. So when I got home I open up my intake pipe and saw thAt my throttle body was jammed and wouldn't open. So I cleaned it out and test drove for about an hr and worked fine like before. Just a heads up it could also just be that. I also had the p2101 dtc code. I checked it when I got home also. I resetted the code now just waiting to see if it will turn on again or not.

 

JDL, hello everyone. I'm new to the forum and have enjoyed reading your solutions to problems, big help. At present I too am having problems with my '03 Tahoe, "reduced engine power." I have been told it is the body control module, but one of you fellas said you bought one and it was not the bcm, it was just a fuse to the bcm. Now where do I find this fuse? I have looked in each fuse compartments and do not see a fuse for the bcm.
Thank you for your input!!!

 

I just received a letter from Chevrolet which addresses this problem. They have extended the warranty on this problem to 10 years or 120,000 miles and will repair it at no charge. If you have already paid to have it fixed they will supposedly reimburse you. All repairs must ne done at a dealer...

Good luck!!

 

My neighbor took in a 2007 Tahoe today with the same problem and showed them the letter I received. They checked her VIN and said it didn't apply to the vehicle. Not sure what the qualifications are????