I have a 1996 Z71 5.7L

I was having an issue where the truck would intermittently have a loss of power upon acceleration...felt very similar to when the governor kicks in when you hit your speed limiter if you know what that feels like. Just an abrupt loss of power and then it immediately kicks back in. This was getting far too frequent, so I took it to the dealer. They said the PCM was malfunctioning and would need replaced...which I don't doubt given the fact that the truck has almost 165k on it.

Anyway, they replaced the PCM and it's been driving great...until a couple days ago. It very randomly and very intermittently still loses power...it's about once a day, but I can't seem to narrow it down to any specific times like during certain levels of acceleration or during certain RPMs...just very random.

Anyone experience anything like this? When it does lose momentary power, the airbag and/or check engine light flashes and the entire vehicle loses power...the radio flickers and everything.

Any thoughts?

 

Id take it back and say they did not fix the problem you paid for.

 

I've already been in touch with the service manager...seems like a really nice guy, he informed me that all GM parts and labor have a 12/12 warranty. So what I'm trying to do is drive it just a little more to see if I can pinpoint when and where it may occur.

 

Ahh, I see.

 

Two offhand guesses would be

1 EGR Valve,

2 Vacuum leak

 

Unfortunate turn of events...I was on my way home from work and the truck just completely went dead. I was turning a corner and I lost all power...but this time it was no flicker, completely dead. Had to coast to the side of the road. No lights, no radio, no power to even put my windows up, no hazards. Won't crank.

So I called AAA and had it towed back to the dealer. It was after business hours so I had to drop it off in the parking lot and hope it doesn't rain tonight since I can't get the windows up.

I'll post an update tomorrow when I talk to the dealer.

 

Yikes, may be a total ECM failure.

 

ECM won't keep you from rolling the windows up. I'd be looking at the battery and all of the ground connections.

 

X2 sounds like a ground issue to me as well.

 

Could just be alternator issues also....