2006 Trailblazer LS EXT shuts off while driving

[justjess]

Hi..
I have a 2006 trailblazer ls ext, and since a bought it two weeks ago it's been nothing but trouble. It shuts off while driving and then it wont turn on. We have to take the pcm fuses out for 15mins just to be able to get it started and out of the way. First round we checked the starter, alternator, change the serpentine belt, oil, filter...put a new battery (red top), and nothing. It worked fine for about 4days and then it started shutting off again. I think the ac has something to do with it. It seems to happen more often when we try to turn the ac on. I couldn't take it anymore and took it to the dealership. They told me that it needs a new pcm. I agree to have it fix since previously when we run diagnostics it showed pcm error, but I'm still concerned if this is even gonna fix the problem. I asked them if they've seen this before and they say no. Which makes me suspicious because I have seen countless situations like mine online, but none seem to find a definite fix for it. Please help!!!!

 

[Mounce]

Does it die while driving, like, above 30mph? Or while driving slow through a parking lot while turning with the AC on?

Pulling the PCM fuses resets the PCM and thus makes it tune itself thinking the throttle body is clean.

What I'm getting to, is, if it dies while going slow while stopping/turning/with the AC on....likely all it needed was a throttle body cleaning. It's very common after having the battery disconnected/PCM fuses pulled for it to randomly die while turning with the AC on.


I'm not sure how you should advance from here since you've already handed it over to a stealership to have the PCM replaced.

 

[MAY03LT]

There have been cases of P0601 (pcm error) causing random stalling so I don't think replacing the pcm was a bad move on their part.

 

[Mounce]

Oh didn't realize "PCM error" was related to a code lol.
Edit:-figured dealership was just taking a stab in the dark

Let us know how it goes, justjess.

 

[Wooluf1952]

Welcome

In case you haven't heard:
http://gmtnation.com/forums/topic/218-welcome-to-gmtnationcom-heres-the-story/

I hope the dealer guaranteed the new PCM would fix the problem. Or, at least, put the old PCM back in and not charge you for the new one.
As Mounce said remove and clean the throttle body should have been the first thing done.
Good luck.

 

[Paul Bell]

Changing the the serpentine belt and oil & filter would have nothing to do with the engine stalling. Unless the battery was bad and not cranking the engine, a new battery would also not fix the problem.

As on these vehicles the A/C system is controlled by the PCM, I would say yes, the PCM was bad. It's rare but it does happen.

How long has it been since they replaced the PCM? Has it happened again?

I'm curious, what did the dealer charge for diagnostic, parts and labor total?