Ford Repair: 1988 Ranger Fuel Injection problem, fuel pump relay, reputable repair shop

Question
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Followup To
Question -
I have an 88 Ford Ranger reg cab 4x2 that isn't running. I get power up to the fuel pump relay but none comming out to the pump. I've changed the relay 4 times with the same result. My fuel guage hasn't worked for a couple of years, but it still ran very well. This problem is driving me nuts. Please help.

Answer -
Matt,

If you have power coming to the relay but not from the relay to the pump, somewhere between the relay and the pump you have a bad wire or your fuel pump is bad. If this does not help, please contact me again and we will go from there. Good luck.

Ken


Ken The wires from the relay to the pump are fine. When I jump from an always hot wire to the wires going to the pumps, the pumps run fine. I also tested them individually & they are still fine. I have installed a new pump/fuel guage sending unit in the tank. At least my guage works now. When I put a test light on the relay termimnal to the pumps there is no power comming out to the pumps. I even checked the wire comming from the computer & there is a small amount of power there. What tells the computer to turn on the relay? How much voltage should be comming out of the computer to the relay? I have been by-passing the relay & the truck runs fine.

Answer
Matt,

It is 12 volts that is supposed to be coming from the computer to the relay.  It sounds like your problem is coming from the computer. You can bypass the fuel pump relay but that can be dangerous as the relay cuts the fuel pump on and off depending on the pressure. I am recommending that you take your vehicle to a reputable repair shop and have them place your truck on a scan tool and see if they can reprogram the computer with the scan tool (sometime...not always, but sometimes, this can be done) Good luck.

Ken