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

Wire Harness Identification

  • Thread starter Thread starter golf4283
  • Start date Start date Oct 9, 2010

golf4283

Active Member
May 30, 2003
1,253
1
39
Orland Park, Illinois
Oct 9, 2010
#1
  • Oct 9, 2010
  • #1
So I bought 2 wiring harnesses off of Ehay from the same person who stated one was a '90 and one was an '89. I'm looking at both received and one still has a tag which identifies it as a '90 so that's fine. The thing is the other harness appears exactly identical to the one with the markings which is leading me to believe it's also a '90. My question is can someone please help me identify the other one as a '90 or '89? Are there the same amount of connectors for each?

The harness is going to be going in my '66 mustang with a 5.0 EFI swap so I also want to know if it's possible to eliminate connectors and just get it down to what I need.

Picture of "known" '90 harness


and this one is not ID'd but has same connectors. I want to know what I can remove from this to make it comparable to a '89 harness is it isn't one?


Thanks!!
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,813
234
Dublin GA
Oct 9, 2010
#2
  • Oct 9, 2010
  • #2
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds
(website host) for help on 86-95 5.0 Mustang wiring Mustang FAQ - Engine Information Everyone should bookmark this site.


Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 5.0 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 5.0 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 94-95 5.0 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

Vacuum Diagram 87-93 Mustangs
The diagram says 88 Mustang, but except for the vacuum line connected to the MAP/Baro sensor, it is the same for all 5.0 Mustangs from 87-93. The 89-93 Mustangs vent the MAP/Baro sensor to open air.
http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif
 
G

guybored

New Member
Apr 11, 2008
43
0
0
South Tx
Oct 9, 2010
#3
  • Oct 9, 2010
  • #3
I am doing the same thing was using a 90 fox harness. At one point it turned on but wouldn't turn off. I followed the link but it don't work. Curious why did you get a 90 when u could of gotten a 91-93 there is alot of infor mostly for those. I learned the 90 is completely different from the other years. I spent a few months messing with it and finally found a 92 harness which was alot easier. I ended up paying someone to come and wire it to turn on because I couldn't. Messing with it a wire burnt and I wasn't getting any power to anything. Didn't spend more than 45 min and it fired up. I am currently removing wires that aren't plugged into anything, and shortening others to hide wires. If i remember correctly TAB and TAD are two of them, there are more but can't remember right now. Google midnightdsign he has some info if you haven't checked it and it will tell you which yo can omit. The oxygen sensor wires are the same as well as the injector harness. There is a website about trucks that has some good info for the 90 harness. Curious (since I can't see link) why you bought a 90 and a "89" harness. If I can help I would be more than happy too, I just don't log in too often trying to finish swap.
 
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