https://ls1tech.com/forums/showthread.php?t=165197

I had my truck in for a PCM upgrade at the dealership. They flashed it with the most current GM code. Once I finally got to open up the new file with EDIT, and adjust things right, I was on my way. Now the problem starts.

Anytime I go WOT it will pull, but as soon as it gets to WOT it falls on it's face and goes into Reduced Engine Power mode. It can be anywhere from a 50 punch, off the line or even sitting in the driveway in neutral or park. Once the code is tripped, the throttle has NO movement whatso ever. It's like the PCM looses all contact with the TB. Looking at EFILive, it doesn't move the TPS, but the fuel cell and timing changes some.

More info .... I have taken the values from the old table and put into the new flash with no positive results. I also raised them and still nothing. I never got this until the PCM upgrade.

 

I had the samething happen to my truck,I cured it by replacing the throttlebody.From what I understand the dealers fix that problem by replacing the entire theottlebody too.See if they will do it under warranty.

 

How was it running after they did the upgrade? Why did you play with it? Do you have nelson's tune? if so, he would flash the newest programming into it. The reason I can see why the throttle doesn't move is because of the engine failsafe (reduced engine power mode). I can't see why gm would put no throttle actuation unless the tb is faulty or something to do with the parameters of the tb and ecm do not match. Did you try and contact the dealer about it? I understand with the exhaust leak you don't want to call them about it but you would need to check and see if they did the upgrade right or if they have been having any probs with the newest software. These are just my .02, just trying to help, if I can. Good luck.

 

Let me make sure I've got this straight. You got the PCM upgraded, then read the new flash with Edit. Then you made changes to the upgraded flash and put the new version into the PCM. Then the problems started... Right so far? And you tried a different flash with the same reuslts?
Don't know if the electronic TB goes bad like that? I guess its kinda hard to test it with the stock tune...
In Edit, all the ETC settings come to mind, plus max mph/sec and calc air flow table.

 

OK ... Whitt, that's what I wanted to hear. Once they guy did the update with the Tech2, he said that he saw the code, cleared it and it was fine. I'm guessing the guy tried to rev it hard. It sat over the weekend while I got EDIT. Once I got a version that would open my file I copied all my tables over and loaded the new file. Now that it would run I can drive it and noticed this happening. I played with the ETC limit and the DTC1514 parameter table with no success.

So far, the service dept is being super kewl about it. I hate to ask for to much though. I was suspecting that is what it was when I was having the wierd problem with the 55+ punch.

I didn't go back to them today becuase I HAD to be places and had things I HAD to do. I will be out of town tomororw, not in my truck because of this though .... so Wed, I will get back in touch with them.

 

Whitt ... is there a TSB or anything that you've seen or heard of with this problem???

 

When you came down for a tune i was a little concerned that tables were copied and pasted in your pcm from another pcm, and i wanted to start with a known good pcm by flashing it, now that it's done, send me the completely stock file after the dealer flash and we'll start over.

later,

allen

 

Mail will be on the way tonite.

Oh .. and for the guy who asked why I didn't get Allen to hook me up .. We tried that. For some reason I couldn't program the new PCM with EDIT, so it went back. Allen hasn't been slacking if that's what you were getting at.

Allen, I'll include the update from Ken in case you need it.

 

Nah, not getting at that, just getting to if you had Nelson's tune or not, thats all. I know he's busy with the gp still I am sure. Still good luck though.

 

Anyone else ... I think I'm gonna go try and get a throttle body out of the dealership tomorrow.