After reading posts i decided to replace the pump and the pump relay (because of a no start). Wen't to pick and pull for both items...especially after autozone quoted 125.00 for the relay. Prior note....i did have a indy shop diagnos and they claimed the pump died. Well replaced the pump and no fire up. Then repaled the relay and she sputtered for a couple seconds then nothing. I can hear the relay clicking after turning the key on and off. I am going back to work on her today and try putting power to the pump drive harness by the ECU. I also have no warning lights on. Hoping autozone will have a code reader i can rent. Any suggestions before i get back into her ? Thanks much, Chris

all you need to read codes on 89-94 V6 sohc is an analoge ohmmeter to get your codes.

Chris,

I'm running into exactly the same thing!

My ECU's is working perfectly, 'cuz I tried it in another Montero, and the relay clicks on Run and Start, but I get no voltage to the pump.

I pulled out the pump, and hotwired it, and it runs OK. Tested continuity from the relay to the pump, and it's OK, too.

Maybe the relay died, but I can't seem to find one at the P&P. Autozone has one? Yikes! $125 is kinda steep. If I can't find one cheaper, I just might re-wire two Bosch relays and pray that it'll work. Keep us posted if you find out what's wrong.

Thanx,
Chris

Im so fustrated !!!! I finally broke the main fuel line nut. Pump dosent spray in accessory position..but sprays when engine is turning over. Wired to the fuel pump test terminal above the ECU and still no fuel pumping out. Totally removed pump and hooked the neg and pos via jumper cables to battery and the pump was humming... As far as spark...new plugs...wires look good...rotor looks good... The pump relay clicks when i turn the key... im lost.... This is my daily driver and im toast not having transportation. MPI fusable link looks good also. aaarrrggghhhh. Please help !!!! I'ts fun to work on rigs when your upgrading or fixing a known problem. Now im totally stumped and quietly losing it.

Pull the relay again and check it per the 89 manual, vol1, pp14-88 and 14-89, which requires some application of power to check voltage/continuity with relay(s) energized. Power to fuel pump is on in ign start via power form ign to relay. Power to fuel pump is controlled by ecu when ign is in run. No power to fuel pump in ign acc. position. It is instructive to examine the relay wiring from the wiring diagram at the first of section 14 (the MPI section).

My relay passed all the tests. I'm REALLY stumped. The ECU's good, the wiring's good, the pump activates when powered, but not when connected.

Start tracing fuel pump power from the fuel pump test wire to the pump, and test the fuel pump ground wire.

Are you sure your optical pick-up or power unit isn't flaky?When I got mine it would fire & cut off. I ended up replacing the optical pick-up. I know some more of you knowledgeable guys will comment;I don't want to see him spend any more money on something that doesn't get his rig running.

what is the "optical pick up" ???
Another discovery....when i pulled the replacement pump out i noticed the rubber boot? on the bottom of the pump must have fallen off and into the tank. I will fish it out and re-install, but could this cause any electrical problems if it was missing?

what is the optical pick-up ? Im still dead in the water and getting an ohm meter to run codes tonight. I really think it has to be electrical...cause when i pulled the pump motor out and jumped it off the battery....it turned. But no turning when i tried connecting the fuel pump jump terminal next to the ecu (before i pulled the pump).