Request from those with 1987 EVTM

[Grand Marquis GT]

I need to know the wiring for the fuel pump circuit. Also, which relay is the fuel pump relay?

I'm looking to trigger the pump relay via an ouside means for my carb swap, if you're wondering. I fucked up a couple wires in my haste. Thanks in advance!

[86VickyLX]

The fuel pump relay is the one with the green plug. If it is the stock wiring harness. Brown is for the EEC, and the other one is for the a/c WOT cut off. The one outside of the plastic housing is the horn relay.

[GM_Guy]

Ground the eca test connector fuel pump wire to turn on the pump. YOU MUST KEEP THE ECM power relay (it feeds the switch side of the fuel pump relay).

The key has to be turned on for this to work (key turns on the ecm relay)

Alex.

[GM_Guy]

What you can do, to have only a fuel pump relay;


Move theYELLOW wire from the fuel pump relay in place of the BLACK/ORANGE wire on the ecm power relay.
Move the ORANGE wire from the fuel pump relay into place of the ORANGE/BLACK wire on the ecm relay.
Now anytime you turn on the key, the ecm relay turns on (as always) but instead of activating the ecm which in turn activates the fuel pump relay, it directly controls the fuel pump.

fuel pump relay:
Yellow= fuel pump power via fuseable link. You do not want to use the pcm relay fuseable link as it is smaller = lower capacity.
Orange= load side- power to the fuel pump.
red=switch feed to relay via ecm power relay.
tan/light green= on/off by grounding either the test port above, or when the ecm grounds the wire to turn on the fuel pump relay.

ECM power relay:
black/orange=pcm power via (smaller) fuseable link.
Orange/black=feed to the ecm and fuel pump relay switch side.
red/light green=from ignition switch
black/light green=ground.

Alex.

[Grand Marquis GT]

I am just now remembering I did this. Thanks a lot Alex and John!

[86VickyLX]

I am just now remembering I did this. Thanks a lot Alex and John!

Is P79 running yet?

[Grand Marquis GT]

No, turns out when I was in my haste, I snipped the wires to the relays. I unplugged everything else, I wonder where the wires to the fuel pump are?

[P72Ford]

You marrying this project?

Lord have mercy.

[Grand Marquis GT]

You marrying this project?

Lord have mercy.

Sorry, unlike some others, I have a life.

[gadget73]

fuel pump wiring and the ignition wiring are all in a plug down there next to the cruise servo. I think its an 8 pin connector or something.

[Grand Marquis GT]

Thanks Thain. I figured that one out by mistake, actually.

I managed to get clicky clicky and fuel pressure last night. I'm happy! Now to finish wiring up the ignition, and i'll be really rockin'!

[Grand Marquis GT]

My MSD box is fried. Luckily, it's under warranty...

So close!!!

[marquisman]

what is up with you and fried boxes?lol

[86VickyLX]

what is up with you and fried boxes?lol

LOL same with me!