Re: wheelin today and a couple of issues
 

You have an interesting PM that includes some information .
Again, if you want to show them the write up to the dealer, feel free, just remove any identification of who sent it.

Re: wheelin today and a couple of issues
 

Thank you. I just called the service dept. They drove it last night and couldn't duplicate the problem. :eek: no $hit!

So I told him word for word what "my source" had said. I also answered one of the two questions. Reduced engine powere was present until the egine was turned on and off. I'm getting you the other info as well.
Thank you.

Re: wheelin today and a couple of issues
 

Just had a another reply from powertrain programming engineer, and she states the P0121 is the code to go after.
When the PCM detects a condition within the throttle actuator control (TAC) system, other DTCs may set due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Keep this in mind when reviewing captured DTC info.

She is also leaning toward a TP sensor, but could be a MAP sensor. She also states that it could have been what I suggested, "a brain fart," that may never happen again. Just a scenario where the inputs got slightly messed up for a second or two, and the PCM could not relate all the inputs. Restarting the engine cycled all back to normal, and the PCM shook it off and went back to normal mode.

Re: wheelin today and a couple of issues
 

Where did you take it to? I want to know if I should avoid the Medved (Wheatridge) service dept the way I avoid their sales dept.

Re: wheelin today and a couple of issues
 

ddaammmnnnn you man f5, I vote you as a Hummer god.

Re: wheelin today and a couple of issues
 

New information. The way John phrased it is it could be a brain fart that could become a stroke. He is thinking there computer program, for some reason, could have become confused by certain inputs, and one of those inputs may have failed temporarily, and could fail totally later.
He is the first person who I have talked to made a statement about the exhaust. The engine parameters are looking for a specific back pressure; usually a small amount of change makes no difference. But, at this altitude, and you possibly doing something normal but strange to a sensor (such as momentarily lifting off the accelerator, then flooring it, or just the opposite),the computer reacted with a reduced power mode. Resetting it by turning it off/on made it reboot, similar to a Windows Brain Fart.
Just another opinion. But he wants to know the final conclusion if there is one.
First guy is still waiting for any information he can get. He is also very curious.

Re: wheelin today and a couple of issues
 

F5- i want to thank you for your efforts on this!!!!!!!!!!!!!!!!!!

You are a huge asset to this forum.

The dealer is reaplacing the TPS due to the "higher up" recomendation.

I smiply stated that this came from someone on a design/ engineering team for these truck and names/ positions were withheld.

After i told them of my connections, they did not hesitate to take the advice and run with it. So we'll see.

I fully plan on running McCalister's gulch this weekend on Sunday and will see what happens @13,000ft.

Thanks again for your help!!!!!!!
Tim.

Re: wheelin today and a couple of issues
 

I really hope that it was the problem. Everything seemed to lean that way, but it was just some educated guesses from miles away.
Glad to be of some help and good luck running the pass.