96 1500 z71 stalling and shut down issues?

[dealwithit]

hey all, so i've had my white gmc sierra for about 6 months now, and its been a great truck :D. it had an issue since i bought it where it would kick down to half power while driving then kick back in, i felt it was the lift pump, replaced it and it stopped doing that. this was about 2 weeks ago. it was fine for about a week but now its stalling all the time while driving, and it will only run for seconds at a time if im driving up a hill. it doesn't really studder or loose power, it just strait up looses all fueling and shuts down. i filled the tank as soon as it started doing this before i went up the long hill to my house and it still did it the same as before. the check engine light also just came on today so i plugged in my reader to it and got 4 codes on the screen

236 TC Boost System
251 Injection Pump Cam system
335 CKP sensor circuit performance
370 Timing reference high resolution

and code 406 but i think thats just a finishing code cause theres no listing for it.

but any who, ill be limping it around for now hoping to figure this out soon, if anyone has any ideas that would be awesome, thanks :D

oh and this truck has had the IP replaced, the pmd remote mounted, and a few other things done. its got 370,xxx kms on it too

[More Power]

You could start with the following thread, which pretty exhaustively dissects the 6.5 stalling problem.

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=2938

Jim

[dealwithit]

ok so my code reader cleared all the other codes but the 406 one was still there. i checked and found 2 busted vacum lines, the one from the vacum pump, and the one from the turbo. i rejoined them with some rubber vacum line and it didn't do much, i did notice alot less black smoke as this truck has been a smokey one since i got it 6 months ago. the code was still there and the check engine light kept staying on, just only showing the 406 code. after some searching and reading i need to test for vacum and bam im getting 0" at idle directly out of the pump, she's toast... ill throw in a new one tomorrow and see what happens.

i really wonder why the check engine light never come on before this, as those lines looked to have been broken for quite awhile. im sure what ever was causing my stalling may show up again soon, i went for a good boot tonight to try and get it all hot again, which is usually when it seems to do it, when its really hot outside and the temps get close to 100.

[Robyn]

The stalling issue is very likely a PMD going bad.

Even when remote mounted they can and will go away.

My 94 Burb has a remote mount and all has been well for 3 years, then out of the blue, the other day it would not restart hot after a short shutdown at the store.

I would install a fresh DTech PMD on the remote mount. Be sure to use some heat sink compound (Same stuff the geeks use to mount the Processor fan in a computer. (white grease looking stuff)

This will definatley take the PMD out of the equasion.

Good luck and keep us posted.

Robyn