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

EEC-IV issues

  • Thread starter Thread starter ekim
  • Start date Start date Apr 29, 2012
E

ekim

New Member
Apr 28, 2012
9
0
1
Apr 29, 2012
#1
  • Apr 29, 2012
  • #1
hello, i have a 92 lx 5.0 and am having some issues with the diagnostic outlets under the hood. it is a 5 speed and the air conditioning has been removed. after buying a obd-1 scan tool i realized that someone had cut some of the wires to the outlets under the hood. i have two green with orange stripe wires and one white with red stripe wire connected to the larger of the two outlet plugs. there are also two other wires with cut ends hanging there. one is white with a red stripe and the other is tan with a green stripe. im assuming one of them would be the ground but there isnt a ground plug anywhere so im at a loss. could one of them of had something to do with the a/c? i was sent a diagram from this site last night but it dosent match up to mine. how many wires should be connected to the large outlet? what colors are they? can someone please look at theres and get back to me as soon as possible. theres no other 5.'0s in the area to compare mine two and its driving me mad. just got the car so dont know whos done what to it. thanks to anyone who might be able to help.
 

OonDeanisS

Founding Member
Jun 16, 2002
902
1
19
Danbury, CT
Apr 29, 2012
#2
  • Apr 29, 2012
  • #2
look through the "surging idle checklist" by jrichker. the wiring diagram is in there. there should only be 3 wires on the large test connector and one on the small STI connector.

http://www.stangnet.com/mustang-forums/threads/help-me-create-the-surging-idle-checklist.698148/
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
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Dublin GA
Apr 30, 2012
#3
  • Apr 30, 2012
  • #3


The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.
 
E

ekim

New Member
Apr 28, 2012
9
0
1
May 4, 2012
#4
  • May 4, 2012
  • #4
sorry about that. im new to this and didnt realize id replyed in the wrong place. the diagrams ive seen dont quite match what i have for wires under the hood. my diagnostic outlet has three wires connected to it. two green and orange, one white and red. the other two wires that appear to be cut are one white and red, and one tan and green. still unsure which if either is the ground wire. does anyone else have this wire color combo on there car? havent found any actual photos online of other cars wiring setups. does anyone know of any other vehicles with wires like mine? included is a pic of my plug and wires to help. the one that currently has the ground plug is two wires spliced together. the wire that actually comes from the harness is red and white. that was done by me just to see if it was really the ground or not. the two greens in the big plug were there when i got the car. the third wire coming from the plug is also two wires spliced together, the one coming from the actual harness is green and tan. sorry for the mess.... i need help.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,813
234
Dublin GA
May 4, 2012
#5
  • May 4, 2012
  • #5
Your wiring is so butchered it looks like roadkill. Without actually being there to see the wiring and chase each wire back to its source, there is very little that I can do for you.

Maybe there is someone else who can sort out your mess. If there isn't , you get to replace the computer wiring harness. That's a time consuming and tiresome job.

If you want to chase the wires, yourself, here's the diagram & a website with other useful diagrams

Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ 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 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 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

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

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
 

RacEoHolic330

I like to dress like a pretty girl
15 Year Member
Mar 4, 2003
4,014
1,698
203
Allentown, PA
May 5, 2012
#6
  • May 5, 2012
  • #6
Wow. Wire nuts... not a good sign. That's probably only the beginning of your electrical nightmare.
 
M

Mark Palmer

Banned
Apr 11, 2012
8
0
1
May 5, 2012
#7
  • May 5, 2012
  • #7
I love this thread already.

 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
May 7, 2012
#8
  • May 7, 2012
  • #8
WOW looks messy. thank goodness for jrichter
 
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