Which one is the fuel pump fuse link?

Creomod

5 Year Member
Sep 14, 2018
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San Antonio,Texas
Ok guys I got my car back together. Last time I had failed compression test due to broken spring but I’m still not “holding fuel pressure “ . Put key on heat fuel pump but gauge drops completely. Car turns on it just Dosent stay on on its own . I’d like to visually inspect that fuel fuse link but I don’t see 4 links to the yellow. I have 3. I’m looking for orange/blue I do see the 2 comming out the test connector but shouldn’t there be a fuse link somewhere on those wires? I also see a orange/blue wire but it goes to somewhere in the front of drivers side harness around the horn and it does run in towards the cab but I don’t think that’s the Orange/ blue wire I’m looking for .
 

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Is this on your stock '92 car? The fuel pump relay and the EEC power relay both get their battery 12V+ from the same wire. Check the fuel pump relay and see if there is battery 12V+ and if there is then I would quit hunting for a fusible link. The next thing is how the fuel pump relay is energized. The EEC relay is energized by an ignition 12V+ and then it powers up the EEC. The same wire that powers up the EEC goes to the coil on the fuel pump relay. The fuel pump relay coil gets its ground from PIN 22 via the EEC. When the EEC detects the engine rolling over via the PIP in the distributor it then sends the ground to the fuel pump relay. The fuel pump relay then outputs 12V+ to the fuel pump and if it's an original 5.0 car it will send that 12V+ back to the EEC (PIN 19) so it knows the fuel pump relay is sending power to the fuel pump.

Really good thread on the whole Pin 19 issue here:

 
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Is this on your stock '92 car? The fuel pump relay and the EEC power relay both get their battery 12V+ from the same wire. Check the fuel pump relay and see if there is battery 12V+ and if there is then I would quit hunting for a fusible link. The next thing is how the fuel pump relay is energized. The EEC relay is energized by an ignition 12V+ and then it powers up the EEC. The same wire that powers up the EEC goes to the coil on the fuel pump relay. The fuel pump relay coil gets its ground from PIN 22 via the EEC. When the EEC detects the engine rolling over via the PIP in the distributor it then sends the ground to the fuel pump relay. The fuel pump relay then outputs 12V+ to the fuel pump and if it's an original 5.0 car it will send that 12V+ back to the EEC (PIN 19) so it knows the fuel pump relay is sending power to the fuel pump.

Really good thread on the whole Pin 19 issue here:

Just thinking it could be a fuse link I have 11.60 v on these ignition wires and pretty much everywhere else, injectors
 
You never mentioned anything about voltages. It literally sounds like the car is starting then the fuel pump is failing for some reason and the car quits running.
 
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You need to start checking for voltages on the FP relay. If they are present then check for voltage on both sides of the inertia switch in the trunk. If they are present on both sides then check the wiring harness plug that is just above the rear of the fuel tank. If voltage is present there you are going to need to drop the tank and check the fuel pump hanger connection and then the pump.

If you do not have voltage present at the FP relay then chase the problem back to either not getting power directly from the battery, not getting voltage from the EEC relay, or not getting a ground from the EEC.
 
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Don't forget the connector behind the driver side kick panel. On my '90 I had loose pins in the connector and would intermittently lose my fuel pump.

I had to squeeze the female pin to tighten the grip on the corresponding male pin. Flawless since.
 
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If you need the Ford wiring diagrams I have them in .pdf and can send them to you. Your 92 should be wired the same as my 93. PM me your email address as the file is 20 Mb.