I try to use the search function for most things but I can't find anything on my issue, so here it goes. Changed the o rings in my 4.8 and now out of the blue it won't start unless I get out and press the Schafer valve on the rail. It doesn't do it all the time but it's got me stumped

 

What O rings?

 

All of them, upper and lower. Got them from gm

 

Fuel injector O-rings? Every o ring on the motor? Specifics help

 

Does fuel come out when you press the schrader valve? Do you have a fuel pressure gauge?

 

Mine was doing the same thing...ended up having to put a return style fuel pressure regulator on and it stopped doing it...it was very annoying ended up smelling like gas everywhere I went because the dam truck wouldn't start unless I bled off pressure from the rail

 

When you bleed it off is any air coming out?

Jake75- so you just converted to a return system?

 

Yeah fuel injector o rings. When I bleed it fuel shoots to the top of the hood. I don't have a gauge

 

Does it do it when the engine is cold?

 

No. Only after I've been driving it a bit