I have an 1985 gs. My fuel pump went out. I turned the key on no sound. I had an extra one from an early rx7 and plugged it in and turned the car over i could see the bowls filling up if i just left the key on. After it started and ran the bowls would just empty. I was wondering if the older style fuel pumps push a different psi then the 84/85?

 

The 84/85 cars used a fuel pump relay and this relay only powers the pump when cranking or the engine is running. The pump should not run if you just turn the key to 'ON'. It sounds like your pump is running only when cranking.

The car uses the signal from the trailing ignition to tell if the car is running. If the trailing ignitor is dead or if the tach wire is disconnected, the fuel pump won't run after the car starts. Does your tach show the RPMs after the car starts?

Your other option is to bypass the fuel pump relay so that the fuel pump runs whenever the key is turned to 'ON' (the 79-83 cars are like this). There is a thread on how to bypass the relay in the 1st gen archives.

 

Yeah the tach works fine.

 

I pulled the fuel pump out of the car and hooked it up to a battery and i got no noise at all. I moved a little tiny bit then stopped... Is this a good hint the fuel pump is bad?

 

I'm no expert, but if you stripped the wires back, touched them to the + & - on the battery and nothing happened. Then that's a pretty good sign....maybe you have a dead fuel pump.
Did you try switching the wires around? - & +?

 

Yeah i switched the wires around and still nothing. So I m thinking the fuel pump is dead. I did what my first post said.

 

You might try a few light taps on the pump with a wrench or something while voltage is applied (bypassing the relay as mentioned).

That worked for me once. The pump sucked in some stale fuel mixed with Seafoam, sat for a couple days, and then refused to pump the next time I tried. (Lesson learned--I should have drained the tank.) I think there must have been way too much gunk flowing into the pump despite the fuel filter and the pump seized up. Didn't do the carb much good either. Anyway, I am still running with the same fuel pump.