[Spartan251]

So I have been dealing with my truck going into reduced power mode every single morning for months now. I get the whole array of throttle body codes. Sometimes it's a different one each day. The most frequent is p2135, 2101, p060e. The kicker is that it will only do it when it is cold. Not engine temp cold, but outside air temp below 50deg. Once it is warm outside i have absolutely no issues. I have replaced the pedal, throttle body, tb pigtail, grounding blocks on fender wells, battery, alternator. I can't find any chaffed or broken wiring. I'm starting to think it is the pcm. Do any of you have any other ideas?? It's to the point that I want to light my truck on fire by the time I get to work (which is only 15min from my house, and most mornings it's gone limp mode 6 or 7 times).

I've searched and am at a loss other than replacing my pcm.

 

[cart7881]

Before replacing the PCM it would be a good idea to check powers and grounds at the throttle body and the PCM. However that would probably not be easy unless you have a heated garage. One thing to do would be to get a hair dryer or heat gun and warm up the PCM, before starting, and see what happens. If the issue is directly related to outside temperatures, it might provide a clue. If that doesn't produce any results, try heating along the wiring harness.

 

[Spartan251]

I hadn't thought about taking a heat gun and warming up the pcm first thing in the morning and seeing if it still does it. I will probably have to try it for a couple days just solidify that it is in fact having an affect.
It's frustrating, some mornings I am almost all the way to work before it acts up, other mornings (especially when it's been raining and is cold) it will startup fine, but hit limp mode as soon as I put it in gear. Sometimes it's just limp mode, running smooth but no pedal response. Sometimes it tries to kill the engine and it runs like it's about to die.

 

[cart7881]

Other than the PCM, it could be an issue somewhere in the wiring. The code P2135 indicates an open or high resistance in one, or both, of the throttle position circuits The P2102 is set because the PCM sees an indication that the throttle position is not what it predicts. Could be the result of P2135.

There isn't much in the throttle position circuit, other than the PCM, the throttle body and the wiring. The accelerator pedal position sensors only feed info the the PCM, so they are only remotely connected to any throtttle movement. They both are oin the 5 volt reference circuit though.

I sent you a message.

 

[Spartan251]

I thanks, I saw your message and will shoot you an email.

 

[Spartan251]

Well it's 35degrees outside completely dry night. Truck won't come out of reduced power mode at all. Throwing just a P2135 this morning. I made sure all grounds were solid yesterday. Will check resistance on the wires when I get home from work.

 

[spaddman]

What year is your truck? There was a known issue for certain year trucks concerning the reduced power mode only happening below certain temps. It happened to my 2010 Colorado CC 4wd. It was also throwing the P2135 code. I have attached a pdf scan from my repair sheet from the dealer. GM labeled it as Special Policy 11273.

 

[Spartan251]

I pulled the tb and plugged it back in so I could visually see it the butterfly adjust when I cycled the key on. No such luck, it looks like the pcm jammed the throttle body shut. I grabbed the one that came on the truck when I bought it and it's definitely open a little more. If you shake them they both sound like something is loose and rattling around inside the stepper motor box. I'm wondering if my pcm freaking out caused damage to the stepper motor teeth. I am going to warranty out the newer one today. Just for the hell of it I put the old one back on and I have throttle response again and no codes...for now.
Stay tuned...

 

[Dragon08]

Well this is a long shot, but I had something of a similar problem in cold weather a while back. Turned out to be a loose fuse. You mentioned the heat gun, and that is when the brain clicked for me.

Crank, No Start w/ code P1682 - Resolved

This week I experienced a No Start on my '10 Colorado I5. Multiple tries at the key produced only a very short sputter, then fruitless cranking. It happened to be the first really chilly morning of the season. I think it was like 26 degrees or so. My reader picked up the P1682 code, though...

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