Well a buddy of my recently aquired a 1986 Iroc Z for free from his aunt. The car has been sitting for 6 years, and we are in the process of getting it back on its feet right now. Surprisingly the car starts and idles fine. But dosent like to turn over 2k, first thing we checked was the fuel pressure and sure enough with the key on it is at barly 20psi. Under throttle it is all over the place. So far we have changed the fuel filter, so whats next the fuel pressure regulator?

Also what are the stock specs for fuel pressure with the key on, and with the car running?

 

You need to post the induction system of the car!

 

sorry it is a TPI car

 

These are TPI numbers at the bottom...

 

20 psi is not enough

 

I know its probably the pump, but is there anyway I can be 100% sure its the pump and not the fuel pressure regulator?

 

Yes. Look at the chart I gave you. It lists a pump pressure that is determined with the return line clamped. Of the 2 going to the motor, it is the smaller. Worst case, if you clamp it and get 0 pressure, it is the other line.