Hey everyone I have a 1999 GMC Jimmy-Envoy. It has a 4.3 in it. Bout it knowing it had a bad fuel pump (No Pump Whine) when the key is cut on. Put a new pump in and it primes up but truck still wont crank. I think I might have mixed the 3 lines up on the tank when I re installed them. Plus I was doing it in the dark with a flood light shining in my eyes! But enough excuses lol! Does anyone know what the connections are that the 3 lines that go to the tank are? Any help will be greatly appreciated!

 

Are you saying the starter does not turn the engine over at all?

The three lines to the tank are +12V, ground, and fuel level power....I think. Now what each is within the connector I am of no help....sorry. Should be able to determine which is which using a multimeter though.

 

No fuel pump primes and starter turns but wont start at all....

 

The thicker wires are for the pump, the thinner are for the sender

 

I took the fuel test port behind the throttle body off and put 12V to the fuel pump test port and it pumps fuel all the way to the test port. Is the cap supposed to have a little pin press thing or just be like a valve cap style? Only thing I can think now is FPR?

 

Ok if yourgetting gas to the testport that's good. Try spraying some starting fluid in the throttle body. If it starts at all you may be right or it could be the spider

 

Haven't done the FP on my blazer but I've done a few on other cars.

First off... I've read on these forums that when it comes to fuel pumps, ac delco is the way to go... trying to save money there is a no go.

Second... I'm assuming you think you mixed up the fuel lines not the electric lines? If so, turn the key to the run position, then check the shrader valve near the intake and see if fuel squirts out of there, if it does the FP is likely installed correctly. If you crossed those lines up, and the pump is running, that means you're pumping fuel somewhere it's not supposed to go... you can probably find that by smell.

3rd... change the fuel filter if you haven't already.

4th... if you have never heard the vehicle run, and it turns over, but doesn't start, new fuel pump... the next thing i would check would be the spark plugs/wires/caps/rotors. If those check out fine, I'd go for a compression test.

Hope this helps :-)

 

Ok lines are not crossed. Put those back together right. Now I pulled off intake manifold top. If I cut the key on with the fuel rail pulled out it sprays fuel. Want to check the spider injector but having a hard time getting the big line back in the hole. Could it be the FPR or the whole spider assembly?

 

Hard to tell at this point u really need to get a fuel pressure tester!!! Really u know its getting fuel but..... How much is the question? Did u try starting fluid? Before u started pulling it apart?

 

Yeh i could put starting fluid in the throttle body and it would kick over and run for a minute. Just hooked the lines up to the spider and pulled a nozzle and nothing comes out....