Truck will not start!! Very frustrating!!

[JCShipkowski]

This is very frustrating let me tell you!!
Engine Performance problem
1993 Oldsmobile Bravada 6 cyl 4.3L Vortech CPI... Automatic 188000 miles

Ok....I recently replaced my ,fuel pump,fuel pump relay and battery(twice) to make a long story short...I have a brain wracking problem with my truck..it will not start without jumping the battery...and I can hear the fuel pump engaging when I turn the key to the run position,as well as it is also turning on when I turn the truck over..The truck will sputter but will not start. I have absolutely no pressure at the fuel schrader valve when key is in the run position,but fuel does come out when cranking engine over!!...I have also replaced the fuel filter as well...I have these symptoms....

SYMPTOMS:
1. Engine cranks fine but won't start.
2. Engine runs fine once started.(err jump started)
3. Hooking up battery charger or jump starting helps get it started.
4. Turning Ign. key On and Off several times may help get it started.(when warm out)
5. starts soon after it was last running.(although with some difficulty)
6. Won't start in cold weather or after sitting for 24 hours or more.
7. You can hear the pump running and it's quiet and consistent sounding.
8. No pressure at the fuel schrader valve when key is in run position .. Help!!!

[inafogg]

i would try to spray carb cleaner in the air intake(throttle body)to see if this helps
you could have a fuel pump on is way out.although this does'nt explain it running fine once its started/running unless its because of cold weather.but its an easy way to see/eliminate the pump.

[JCShipkowski]

Yeah I mean my query is why would the pump work right when started,but not on startup? It is pretty cold up here right now, not sure how that could effect things since I'm not a certified mechanic or anything.It's a brand new pump,new relay,and I've switched the battery twice...I checked the ground today and the connection to the pump...I wonder if any of these symptoms could point to a bad fuel pressure regulator? But the no pressure at the schrader valve is what's stumping me on this one....

[Chris Stewart]

The fuel pump only runs a few seconds then shuts off after turning the keyswitch on but not starting.
The fuel pressure spec is 55psi to 58psi on the CPI motor.

The engine will run on very low pressure after starting but anything less than 52psi will hard start/no start.
I've used my fuel pressure check kit to retrieve lawn mower fuel while the engine was running...really drops the pressure but doesn't stall the engine.

Since you can hear it run, I'd suspect a bad pump, even if it's new.