doofus

Hey guys. I posted this on the truck side also, but since the engines are similar I thought I would post here too. '05 Sierra, stock 6.0 with STS turbo, meth injection, custom I/C. I have recently had trouble with starting the truck, both cold or hot. If I try to start it cold I can turn the switch and release it but the starter remains engaged for about 5 seconds. If I drive it and get it up to operating temp and then park it and shut it off, then try to restart it say 20 minutes later it takes 10-15 minutes to get it to fire. It is driving me nuts, and I was wondering if any of the STS guys on here have had any problems like this. It may not be turbo related at all, but any input is greatly appreciated!!! Thanks....

veee8

iTrader: (40)

Do you have a remote starter on the truck? There are multiple ignition circuits that go through relays, sounds like something under the dash to me.

doofus

No remote starter. I haven't had time to troubleshoot anything, but I did just have a warranty issue taken care of concerning the left rear window. They said it was a wiring problem, and I have wondered if they might have boogered something up. Might not be related though. Once it fires up it runs perfectly, no problems at all. Anyway, thanks for the reply. I need all the help I can get!!

BigJls1

work truck did the same thing, it was the fuel pressure regulator. its right above the intake on trucks......at least our 2002 model was. 65.00 at autozone and took like 2 minites to change .

veee8

iTrader: (40)

Yes! I have changed several of those out on the LS trucks, forgot about that one. But a little confused about the starter staying engaged after letting off the key. Thats why I was thinking ignition related.

veee8

iTrader: (40)

Easiest way to check if it is the regulator, is to pull the vacuum line off, if it has gas in it, bad reg.

doofus

Thanks for the replies!! I was told that the starter remaining engaged was due to a starting timer inside the PCM. When the switch is turned to the start position it starts the timer which in turn counts down a predetermined amount of time and then stops at "zero" or when the engine fires, whichever comes first. That came from a GM Tech, and I give him much credit. Perhaps the cars are the same way, my Formula has never done it so I don't know. As for the regulator, is it in the front of the manifold with the port for pressure testing attached? If so then I'll check it next. Thanks again guys!!

veee8

iTrader: (40)

Yeah, it is a little round regulator, just pull the vac line and inspect. The regulator itself is pretty basic, the diaphram inside is what fails. The trucks use a different system than the cars, the various modules communicates through the CAN network. I will buy into the built in timer. Really looks like your regulator is what is giving you fits. Let us know what you find.