sorry if this is the wrong forum, i didn't see anything on the board for "general troubleshooting"... i've got an '00 Suburban 1500 w/the 5.3L... for a while it has been idling very low (and rough) and then recently started dying a lot while driving... i have a buddy who works at a GM dealership and he took it over there for me (so it would be free!) and the mechanic found a leaky pressure regulator on the fuel rail... he replaced that and for about 3-4 days everything seemed perfect... the idle was up around 550 vs the 350-400 that it had been at... however, yesterday it started dying again... it runs and idles fine, but as you're cruising along it will just shut off... not under acceleration or decel, just normal cruise... the mechanic mentioned that the fuel pressure regulator was a chronic problem (he was surprised that mine made it to 88k miles, they usually go out at 50k) but he also said that "the throttle body" is an issue on this truck... he said i'd have to drive it to find out if it does it anymore... anyway, my question is, does anybody know what "the throttle body issue" is on these things? and what's the solution?

thanks,
Jeff

 

I posted a thread on here about idle problems with your tb - use the search - It was a couple of months ago

 

thanks, i found your post finally but only by going to your profile and listing all of your posts... i had searched before i made my first post for "idle problems" "stalling" etc, but didn't turn up anything...

after reading the description, i'm not so sure that this would cure my problem... the idle itself is pretty smooth after fixing the fuel pressure regulator, but cruising down the interstate with the cruise set at 60mph, the thing just dies... rpms are approx 2000 before this happens, so the idle logic shouldn't be doing anything...

 

fuel pump ?? - ok when cold and idle ??
problem hot and running ....
Might want to put a fuel pressure gauge on it
tape it to the windshield - check press
before it dies.....just a thought