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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

87 motor in 89 gt

  • Thread starter Thread starter wjhart3
  • Start date Start date Nov 23, 2007
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wjhart3

New Member
Nov 23, 2007
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phila pa
Nov 23, 2007
#1
  • Nov 23, 2007
  • #1
please help, i put a 87 331 stroker in 89 gt roller, i had to use the 87 engine wiring harness, but the fuel pump wont work. the 89 body has an extra plug with 7 wires comin out of it, i beleive this is for the eec relay, can i wire this so fuel pump work? the fuel pump relay has no power on the red wire but the pink is hot. do i have to switch to a 89 wiring harness for this configuration to work?. the 89 had the wiring harness removed so i used the one from the 87. i would like to switch to mass air but want to get it runnin --the eec relay is missing -should it run without it and will it run with it?any help would be greatly appreciated---
 

85ragtop

BTW, I like dudes.
10 Year Member
Nov 29, 1999
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NC
Nov 23, 2007
#2
  • Nov 23, 2007
  • #2
This is falls under 5.0 tech.
Thread moved.
 

tbovee

Member
May 22, 2006
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Fredericksburg Va
Nov 24, 2007
#3
  • Nov 24, 2007
  • #3
Try comparing the 2 harness's and see what the differences are. You only need a few wires to get it running and some very good grounds. I believe its a constant 12 v source, a ign / cranking source and a connection to the sol. "blue wire?" and the grounds. Look at the diagrams and you can see what you need to get the fuel pump going and power to everything else.
http://www.autozone.com/az/cds/en_us/0900823d/80/16/71/3c/0900823d8016713c/repairInfoPages.htm
http://www.autozone.com/az/cds/en_us/0900823d/80/19/59/5a/0900823d8019595a/repairInfoPages.htm
http://www.veryuseful.com/mustang/tech/engine/
 
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wjhart3

New Member
Nov 23, 2007
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phila pa
Nov 24, 2007
#4
  • Nov 24, 2007
  • #4
eec

thanks for reply, theres no plug on the 87 harness to go into female plug on the on the pass side compartment where the computer is.i believe the eec relay is missing so i gonna buy the relay before i short sometin out. the a/c relay already got fried under the hood but the wires were touchin..thanks for the links i bought the shop manual from ford and it doesnt have the wiring diagram----
 

Prime Lord

Crappy Default Title
Founding Member
Sep 19, 2000
2,137
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Denver-ish
Nov 24, 2007
#5
  • Nov 24, 2007
  • #5
There is a fuel pump relay (brown I think...or green) that is tucked WAY up in the passenger side access to the ECU. Reach all the way up by the firewall and you'll find it. Make sure its not just an empty plug and that it has the relay plugged into it.
 
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wjhart3

New Member
Nov 23, 2007
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phila pa
Nov 25, 2007
#6
  • Nov 25, 2007
  • #6
fuel update

found the relay tucked up by puter, its in there, checked the power on the red wire to relay under seat and its got power and the pink also has power, ordered the eec relay which was missing next to computer and thinkin fuel relay under seat is bad. the wire on pin 22 has also come out so goin to fix that and see what happen. the pump will run when its jumped at the relay so its in this wiring somewhere--
 
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