Hey guys need help here.
just got a 94 gmc 1500 with tbi 350. it has sat for about 4yrs. needed starter and battery. replaced those, turned key on and could here the fuel pump run in tank. tried to start it, and on the 4th turn it fired up. it was ideling and running pretty smooth for an engine that sat. after about 5minutes it died. well i thought needs gas, ran out, put about 2-3 gals in it. and now it wont run, it will start if u pump it like a carbed engine,but u have to feather the throttle, to keep it running. and if u give it lots of gas, it wont respond in kind. ie wont rev up. it just tries to die. too much dies, too little dies. ive checked the fuel filter and blow air thru it. the gas does smell old. do u think it could be too old to support the engine running? or is the fuel pump too weak to provide enough to run. seems like it would not run at all if this is case. i can still hear pump running. give me some direction, as im already in troulbe with the wife for this truck. i told her all it needed was starter.
tks,
doc

 

Well, sounds like a good ole troubleshoot. Things that go through my mind as default are usually, Plugs, exhaust o2 sensor, and most fuel components.

 

i imagine your fuel pressure is low...it fired up..but...the fuel pump is attatched to the sender with a 3 inch rubber hose...older trucks,that hose splits,and half your fuel rains back down in the tank.

the only way to know without removing the pump would be to check the pressure.