i have a 87 5.0tpi iroc when i plug my fuel tank in my car will not start not even a single fire when i unplug my tank the wires to the sending unit the plug under the car in front of the tank my will run at idle but obviously starves for fuel when i get the gas.
Why would plugging my fuel pump in stop the car from running?
Thanks for your help i need my baby running before snow flies and the weather is still good!!!!!!!!!

 

Ruptured diaphram in fuel pressure regulator flooding the engine with gas thru the vacuum line would be one.
Shorted fuel pump drawing the voltage down and de-powering other items in the circuit would be 2.

 

there is a sensor? undernieth the center of my plenum that goes into the intake with a single black wire i think it is sharting out could this cause the problem and what the **** is it? thatks for the reply ive bought a new regulator just havnt taken the old one off next project

 

can i run a direct switched hot wire to my fuel pump? Do i just tap into the grey wire that goes into the fuel pump? Do i need to do a different ground i dont need my baby burning up!?

 

Check out the FPR first. It's much more common.
No. If so, unplugging the F/P would have no effect.