[Jozuah]

What? Serious? No one even has a guess about this?

now im no genius but im pretty sure this should have vacuum till you hammer the throttle then as the plenum pressure drops to nothing the regulator closes and keeps all the fuel there (pre-bypass) to feed the injectors the extra fuel they require at WOT.

prosphoto will chime i hope but im pretty sure all the regulator systems work this way ,i may have it completely backwards lol.. if there wasent 13" of snow on my truck ATM i would go see for myself tomorrow i certainly will though i need to clean my air filter.
Josh

 

[Jozuah]

With that line connected, when you remove the line form the regulator, there should be vacuum at the line, not the regulator.

No vacuum from the source is definitely a problem; the regulator will be supplting maximum fuel pressure

yessssssssssssssssssssss, im still no genius.

 

[Jozuah]

Im guessing completely here, but is there a chance the fuel pressure regulator is broken and therefore blocking off the hole 100% of the time? I dont know if I have vacuum on my 02, cant check it either b/c its 300+mi from me.

And Josh, I dont even know if you have the connection, it was late 03/04 IIRC that GM stopped putting a hose btw the regulator and the resonator.

Is this causing you any problems Steve, low idle, loss of power, loss of mileage?

i have the line