I just wanted to check and see if someone might be able to come up with some other reasons why my fuel pump will not come on. The fuse by the radiator is good, the relay is good, and I just installed the pump, a brand new Walbro. Can anyone think of some other reasons why it wont come on, maybe something out of the ordinary? It is a 1990 GTA , 350 , TPI.

 

You probably have already checked, but the first time I changed the pump in mine, I left it unplugged. You might check the connector under the car right in front of the gas tank.

 

Why did you replace the old one?

 

It's plugged in, and this is why I replaced it (my post from tech/gen engine)I had just finished installing a cam, headers, new injectors and a few other things, got the exhaust hooked up and drove the car to work and home. The next day on the way to work the car died like it ran out of gas, which it was extremely low and I was going to stop for some but did not make it. When it still would not start after putting gas in it, I splashed some in the throttle body and it ran long enough to burn what was in there, I then realized that I was not hearing the fuel pump come on. So I checked the fuse and replaced the relay and finally the pump itself. One more thing, I ignorantly did not have an o2 bung welded onto my header, so when I did drive it to work it was running rich as hell due to no oxygen sensor. Although I dont see how that could have anything to do with the problem I am having now. I already have the wiring harness and stuff for a heated sensor to fix that. The guy next door who has an 89 Camaro swears it has something to do with the VATS and claims his car did the same thing and he somehow bypassed the system or something and says he can do the same with mine, I am not one for rigging things on my car and would rather fix it right even if it costs more money. Sorry for the novel, but I HAVE to get this car going.

 

sounds similar to a problem I have at work. 91 GTA no crank/mo start. Only differance is the fact that the fuel pump comes on.

Chris

 

definetly not VATS if its cranking. best way to track down the problem is to check for voltage at the commector bythe tank and go from there.

 

Ya, check for voltage at the pump like Mike suggested as well as check for voltage at the relay.

You can also jumper 2 pins on the ALDL connector to get the pump to start up, gotta look up which ones they are since I can't remember.

 

After verifying that I had power to the back of the car , I figured it had to be the sending unit. So, I dropped the tank again, tested some wires and the pump itself and found that it was a bad connection where the wires plug in to the sending unit from the pump (the round part where all the lines go through that sits on the O-ring) The prong sticking down that is for the gray wire was filthy and so was the connector that goes to it. I cleaned them up and now it works great. I still can't believe it was something that simple, but I am glad it was! I can't wait to take this thing to the track, it seemed to have much more power today than when I first got it going before the other pump died.
Thanks everyone for helping out!