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Electrical EFI Harness question

  • Thread starter Thread starter Husky44
  • Start date Start date Dec 24, 2012

Husky44

10 Year Member
Sep 27, 2006
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Tacoma, WA
Dec 24, 2012
#1
  • Dec 24, 2012
  • #1
I'm putting all new loom on my EFI harness (old stuff was brittle and looked like crap). I came upon an interesting issue, and not sure what to do with it. Would really appreciate some input from those who either have significant wiring experience, or have been inside the EFI harness before. I can speculate that this isn't right, but am looking for more than speculation:

Just downstream from the center section on the driver's side, all of the red wires are stripped of insulation, bundled together, and the entire stripped of all of the wires is wrapped up in a tar-like substance.

Is this the way it's supposed to be, or did someone create some sort of monstrosity after the fact? Since each injector has a red wire connected to it, I guess it's possible that Ford wanted them all to join together, but it sure looks funky.

This harness came off a running car, so it didn't appear to impact how it ran.

Also posting this in the main 94/95 section where I normally hang out, but though I'd post here as well to get more feedback. Harness is from a 91 LX, going into my 67.

Thanks, and Merry Christmas!
 

gearheadboy

15 Year Member
Jan 15, 2003
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84
Greencastle Pa
Dec 24, 2012
#2
  • Dec 24, 2012
  • #2
Don't know this particular harness that well but I am awake and will offer my opinion. It sounds like a factory splice, the correct term eludes me right now. The goo is probably antique tape or the like for insulation. My guess is black tape it good and add your new loom and forget about it. Maybe someone else has seen this particular splice before and will know for sure.
 
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Husky44

10 Year Member
Sep 27, 2006
865
104
74
Tacoma, WA
Dec 25, 2012
#3
  • Dec 25, 2012
  • #3
The more I think about it the more I'm convinced that it is factory-- it just doesn't look like something the factory would do. The goo was definitely not tape, it was some sort of putty. I'll put it back together tomorrow.

Thanks!
 

jrichker

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Dec 25, 2012
#4
  • Dec 25, 2012
  • #4
Sounds like a factory mess, but it probably came that way.
Here's some diagrams to show where all the red wires go in case you have any problems.

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 & pin out
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

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif
 

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Husky44

10 Year Member
Sep 27, 2006
865
104
74
Tacoma, WA
Dec 25, 2012
#5
  • Dec 25, 2012
  • #5
Good info, but I'm no expert on reading wiring diagrams, is it safe to assume that the fact that all 8 injectors feed off the same power line indicates that this unusual connection is correct?
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
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Dublin GA
Dec 29, 2012
#6
  • Dec 29, 2012
  • #6
Husky44 said:
Good info, but I'm no expert on reading wiring diagrams, is it safe to assume that the fact that all 8 injectors feed off the same power line indicates that this unusual connection is correct?
Click to expand...
Yes.
 

flyinhigh90

Member
Nov 23, 2012
107
1
19
San Bernardino
Jan 1, 2013
#7
  • Jan 1, 2013
  • #7
u can find a whole engine harness in ebay all day long and ur better dong that and just puttinf new wire loom on that.
 
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