I have a 1991 Montero. It’s a four door, five speed, 6g72 V6. The problem is that there is no voltage to the fuel pump when the ignition is in the run position. Voltage is present in the start position, so the truck will start then immediately die. When I hook a jumper wire from the battery to the fuel pump check terminal, the truck runs.


I have tried changing:


Distributor (cam/crank position sensor inside)
Computer
Engine Control Unit
MPI Relay
Throttle Position Sensor
Air Idle control
Mass air flow sensor
Fuel pump
Fuel filter
Coil
Ignition switch
I have checked every fuse in the side of the dash
The three fuses on the positive battery terminal
Every relay on the passenger side kick panel
The three fusible links on the passenger fender are fine

It may also be relevant to mention the heater blower motor, brake lights, blinkers/hazards do not work. The check engine light is not on when the vehicle is running. I bought it in the state that it’s in now.

Is there a fuse or relay that I have overlooked? Is there a way I can rewire fuel pump voltage but still have it be regulated (varied) by the computer?

It would be a shame to part it out, but that’s what I’ll have to do if I can’t find this wiring gremlin.

 

Did you ever solve this riddle? I am have in the same problem with my 90 LS. Power to fuel pump in Start position but not in Run position.

 

pull your ecm remove the cover and check for burnt caps