1990 Chevy 1/2 Ton Starting Problem

[sarah1980]

I have a 90 chevy 1/2 ton 4.3 l will not start intstalled new fuel pump,fuel filter and wont start but if i pour gas in the carburator it will start and then die right away,any help would be appreciated.

[rodram]

Hello and welcome to the GM-Truck forum. It sounds like for some reason there is no fuel delivery to the engine (until you pour in a little). It is possible that a fuel pump relay is not working, fuel pressure regulator is not working, and possible that (even though you installed a new one) maybe the fuel pressure is low.

 

If your truck has the original 4.3L in it, I believe that it will be fuel injected and there should be two injectors delivering fuel into the throttle body (technically not a carburetor)

 

I would start by checking for power to the fuel pump when the key is on. You should/might hear the pump pressure-up the system for a second or two as soon as the key is turned to on. When trying to start the engine the two injectors should deliver a steady stream of visible fuel into the throttle body. When trying to crank the engine the fuel pressure should be about 12 to 15 psi .... (9 or 10 psi is too low).

 

These are some basics to check out ... there may be some other more complicated stuff going on, but these should be checked and ruled out (or corrected) first.

[GMstrong]

How is the fuel spray?Did you do the fuel filter also?FPR could be dirty and gooked up its really easy to do just 4 small corks the spring is a pay in the ass though.