Cranks but no fuel. Replaced relay,fuel pump, oil pressure sensor still nothing. Is there any other sensor that could cut fuel in any way on a 1991 RS 305 tbi? Rear impact sensor?

 

 

Original TBI injectors?

 

1. Does the fuel pump run for two seconds when the key is turned from "off" to "run"? If the fuel pump primes, it's not the fuel pump relay. If the pump runs when the engine is being cranked (has oil pressure) it's not the oil pressure switch.

2. Do you have spark? No fuel, no spark = distributor or wire harness problem. ECM requires distributor pulses to turn on the fuel injectors. No pulses, no fuel spray.

 

Can't hear the fuel pump run or prime. I've got spark. What is the sensor on The back of the rear end pumpkin? This problem happened driving on a hot day on the freeway. Just lost all fuel all of a sudden. Replaced the fuel pump then ran good for 1 1/2 hour drive then lost all fuel again.

 

What is the voltage on the fuel pump + wire near the fuel tank when the engine is cranking? Should be within a couple of volts of battery voltage
What is the voltage on the fuel pump - wire near the fuel tank? Should be less than 2 volts, less is better.

Have someone crank the engine while you listen to the injectors. You should hear them clicking. (They won't spray fuel if there's no fuel pressure.)

No idea. Sure you're not seeing the brake plumbing, or the axle vent?

Did you replace the short wire harness from the fuel pump to the fuel pump hanger connector? They're known for corrosion.

I figure it's most likely you have a bad wire--corroded connection, broken, pinched, something like that--between the engine compartment and the fuel pump--or between the fuel pump and ground. 'Course, it could just be a plain ol' defective pump. If it was a plugged filter or filter sock, you'd hear the pump run during "prime".

 

 

 

Can I access any fuel tank/gauge wire’s from underneath?