I am all mesed up on my fuel pump/relay wiring. (89 mustang)
So of the write-ups i have read said to send the 2 wires pk/b (from the black connector) and t/lg from the green connector by the EEC) to the fuel pump relay. Problem is, I am pretty sure the fuel pump relay is hard wired into my harness (Correct?) , and so do i just splice these wiring into the pre connected fuel pump relay? what wire?

also 2 more wires, these are by the coil plug, one is blue with a fuseablie link, where does that go (hot, run, whatever)
Another is all black with a ring terminal (pretty sure its a ground) it bottle necks into a bunch of black/green wires.

Help me!

the fuel relay on my harness was not 'hard wired' in. I ran those wires (from the plug by the comp.) to a Bosch relay, then to the pump.

A big black wire with a 'ring teminal' is just SCREEMING ground wire.

Dunno about the wires by your coil.

Originally posted by welndmn
I am all mesed up on my fuel pump/relay wiring. (89 mustang)
So of the write-ups i have read said to send the 2 wires pk/b (from the black connector) and t/lg from the green connector by the EEC) to the fuel pump relay. Problem is, I am pretty sure the fuel pump relay is hard wired into my harness (Correct?) , and so do i just splice these wiring into the pre connected fuel pump relay? what wire?

Help me!

I don't know what harness you have, but on most factory late model 5.0 mustangs, the fuel pump relay is physically located under the drivers seat, which in in the chassis harness. The biggest confusion I found when I set up my fuel pump relay, was that I thought the relay was part of the engine wiring harness.
Run the wires you have to a regular relay using the PK/B as the source voltate(Hot all the time, the 87connection on the relay) and the T/lg is the signal from the computer to the relay(Hook that to the 85 on the relay). Then you will have to run a ground to the realy(to 86 on the relay) and a output from the relay(from the 30 on your relay) to your pump.

If you are still having problems with your relay, e-mail me and i can scan the factory wiring/troubleshooting electrical manual and send it off to you.
Hope that helps.....

B

hey Mark, I can help you here...

The fuel pump relay is not part of the 89 harness. It is actually under the seat (for some reason). so you'll need to make your own harness there. Pink and black, I believe are the input power to the relay and to the computer. Make sure it is fused! Tan and green go to the ground. GROUND IS CONTROLLED BY THE COMPUTER! That's how the computer controlls the fuel pump. The switched power goes to crank and run.

The black ring terminal that goes to the black/green wires is indeed ground. IT MUST GO TO YOUR BATTERY!!!!! Trust me, going to a good body or frame ground is not good enough!

Also, be careful, If I do recall there was a black ring terminal'd wire that went to power on my 90 harness. Blew out a computer because I assumed it was ground.

I don't recall a blue wire and there is no reference to it in the Ford manual (which is based off of the 93 harness). You may not need to mess with it.

If you need more, I have diagrams on EEC and FP Relay wiring. Also, if you aren't going to Bosch relays all around, I have spare relays you can have (I changed all of my relays to the Bosch relays so I only had to carry one spare and it was easier to wire).

-Jack

Hmm, ok, Thanks guys i will have to check out my harness at home and ask mroe questions.
God, now i wonder what that damn relay is, that i thought was an fuel up relay

What color? There's Wide Open Throttle and EEC.

-Jack