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Discussion Starter · #1 ·
so ive been having trouble with my 89 gt fox body, fuel pump wont turn on, and no injector power, inerta switch is good my question is at the computer the red wire that supplys power to the injectors, relay and inerta switch has no power coming out of the computer? is the computer fried or is there something that im missing? im at a lose right now, anything will help
 

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EEC relay is the one that supplies power to the computer, injectors, actuators and fuel pump relay coil. You may want to go over the How to Solve an EFI No Start procedure and LUK.
 

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Discussion Starter · #3 ·
After an entire day of testing I was able to find nothing that was posted to be a problem, at the fuel relay I'm only getting 1 wire with power that was the one hooked to the battery, so as of right now I'm at a dead end
 

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Use the attached diagram, you need to trace the FP relay coil IGN ON power supply wire, which is fed by the EEC relay..... located above the EEC as shown in the 2nd. attachment.
 

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Discussion Starter · #5 ·
im having the hardest time getting to the eec relay, would it be better to remove the dash to get to the wiring better?
 

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I'm having the same problem on my 91 5.0 and have been through every check sheet that can be found. Here's where I am:

1. Fuel pump not priming,
2. Replaced FP relay. Still only the hot from the battery. Nothing else.
3. Jumped FP on ECC self test to ground to see if pump would prime, no.
4. EEC relay has 4.5 volts on red wire. But nothing to red wire at FP relay. Also, 12V showing before and after fuselink at solenoid.
5. No power at intertia switch or pump.
6. FP relay does not click. No power getting to it from EEC.
7. Checks continuity and all wires seem good...I get a beep on voltmeter.

Really at a loss as to what to check next. The only thing I know is I should have 12V at EEC relay and only have 4.5. Bad ground somewhere?

ANY IDEAS would be very appreicated!!!
 

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EEC ground. And it grounds the EEC relay also.

At the EEC relay you should have at least one wire thats hot at all times. Normally a orange and black wire. And 3 hot with key on. So check that and tell me what wires are hot. Post the colors of each.

What color was the fusible link you checked?
 

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Fixed. I had nothing on that bolt at all. Looking deeper one of our crew grounded two wires lower on the inner fender and there it was...a blue wire with a fusible link. It was yellow inside the car but once hooked to solenoid everything worked as it should.

Thanks for the heads up. A 4 day project put to bed.

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