Hey guys any help with this would be greatly appreciated. 01 lb7 bone stock, never had a starting issue in the 8 months ive owned this truck. Last night I go to start, strong crank fires right up. Let it idle and warm up for several minutes, throw it in reverse and putters out on me. Crank it over again, cranked strong but not even the slightest hint of the engine starting. Popped the hood and found the wires on top the fuel filter were disconnected, which to my knowledge power the fuel heater. Plugged it back in and same thing, strong crank no start. It wad late when this happened and work late tonight so tomorrow I'll be testing all cm's power and ground, as well as fuses and injectors.. ive read about the passlock issue and want to know how to determine thats my problem and how to fix it. And if its not my problem what else I should check. Taking to shop is an absolute last resort so all the advice I could get would be great.

 

air in fuel, try priming the fuel filter and see if it runs

you need to loosen the bleed screw, pump the button till fuel comes out of the screw then tighten it back down, if it runs then dies again you have an air leak somewhere in your fuel system

 

Yeah, done that already too forgot to mention it tho. Its a good stream doesn't spit out ad if air would be in the lines

 

It sounds like u lost the prime. I know u said u hand pumped it, but even after hand pumping it after u run it dry, it will still have to crank a minute or two and may have to hand prime it again.

 

Ill go back and check it out and give it a whirl. Do you know much about the gm passlock, its pretty foreign to me

 

Is the security light flashing? It shouldn't be that.

 

yeah the security light always flashes, at least until the key is turned, then the battery light comes on. its starting to look like low pressure in the fuel rail after actually getting a chance to get into it, just need to actually test the pressure to be sure... to follow up on your comment on losing prime, it was good when i checked it originally and after now going back in its still steady coming out of the bleeder. changed the filter today, re primed and cranked longer than normal, id say 30-45 seconds top. if you insist it takes a few minutes of crank ill go back to that, i just dont want to burn that starter up.

 

mine usually fires up pretty quickly after re-priming it, it shouldn't crank for more than 30-45 seconds

 

finally got the damn thing.. replaced filter as i said, primed and bled the lines even more than was necessary just to reassure myself that i wasnt messing something up. cranked it for longer than i had been, minute and a half or so and finally fired up.. so thank you for that advice goblin, but im now curious as to how i randomly lost prime like that, and also how the fuel heater wires that connect on top of the mounting bracket came off. i have changed the filter one time about 3,000 miles ago and hadnt had a problem one.. and also why it started up normal the night it happened and ran for several minutes but as soon as i put in reverse it died on me? if you could shed some light on this for me id be grateful because i dont understand

 

The filter lost its prime. U still had fuel in all the lines going to the ip. So when u started it it ran for a few seconds before running out of fuel. And while it was running it started to suck some more fuel up to the filter but not enough to keep it running. IMO, I'd spend the couple bucks and buy one of the PPE bleeder screws that are metal. The bleeder is normally what causes air to get in the system.