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  • Fox 5.0 Mustang Tech

91 5.0 - Engine Wiring Harness

  • Thread starter Thread starter Spieg
  • Start date Start date Sep 19, 2017
S

Spieg

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#1
  • Sep 19, 2017
  • #1
I was poking around the engine compartment trying to find a wiring problem (O2 sensors not getting power). I was looking at the "Salt and Pepper" wiring connectors to see if they were dirty when I noticed that I seem to have 4 of them rather than 2 (looks like one plugs into another via a short pigtail). All of wiring diagrams I have found only show 2 of these connectors... Anyone know why I would have 4?
 

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Sep 19, 2017
  • #2
I'll move this to the tech threads
We also need a little helpful info
Year, mods, miles
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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#3
  • Sep 19, 2017
  • #3
Oh yea, some pics of the duel connections too may help.
 
S

Spieg

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#4
  • Sep 19, 2017
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karthief said:
Oh yea, some pics of the duel connections too may help.
Click to expand...
Its a 91 5.0 GT manual transmission (mileage unknown as it was an engine swap but I guess about 80k miles). Ill see if I can get a couple pictures posted, but its pretty simple really. the wiring from the computer runs into one end of a S/P connector and then at the other end there is a short (maybe 6-8") pigtail which plugs directly into another S/P shaker and then out to the sensors etc... There are 2 separate bundles of wire that each are configured like that with 2 S/P connectors.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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Sep 19, 2017
#5
  • Sep 19, 2017
  • #5
Just so my cartoon mind is visualizing this correctly, you have two white and two black 10 pin connectors?
 

Dan02gt

mazing how much gas smell came from that tiny hole
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#6
  • Sep 20, 2017
  • #6
Sounds like Ford installed the "fix" in your car. This was 2 extensions cables that were used to make the wires longer as the Ford engineers though that the problems with the salt and pepper shakers were due to the wires being to short. It's really just a poor design. You can remove these and clean/tighten the original connectors. All they really do is just add more points of failure to the system.
 
S

Spieg

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  • Sep 20, 2017
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Thanks for the info. I was hoping it was something like that. Wasn't sure if they had changed any of the pin positions between the 2 connectors, but it appears they go straight through...
 
S

Spieg

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#8
  • Sep 20, 2017
  • #8
On a similar note, has anyone used the Ford Racing harness (M-12071-A50) to replace the stock harness? It looks like it gets rid of a lot of connectors and simplifies the whole thing quite a bit.
 

imp

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Jul 13, 2017
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#9
  • Sep 20, 2017
  • #9
Pardon my ignorance: What are "salt & pepper shakers" ? imp
 

Mustang5L5

That is…until I whipped out my Bissell
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#10
  • Sep 20, 2017
  • #10
The harness is great for swaps into different cars, but seems redundant on a fox. There really isn't much you can delete to make it worth $600 IMHO.

As for the 4 salt and pepper shakers, disconnectbthe extension harness and ditch it.
 

imp

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General karthief

wonder how much it would cost to ship you a pair
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#12
  • Sep 20, 2017
  • #12
imp said:
Click to expand...
At the back of the upper intake, between the intake and the firewall there is a wade of wires with a black connector and a white connector, they are referred to 'salt and pepper shakers' because of that.
 
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S

Spieg

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#13
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I think the main purpose for them is to make it a little easier to pull the engine, but they sure do cause problems for me when they get dirty. I guess I should have mentioned this engine is in a Jeep CJ (rock crawler). Hope it isn't sacrilege to say that on a Mustang forum...

If I don't get the replacement harness, I'll probably ditch the S/P connectors add some Weather Pack connectors.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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#14
  • Sep 20, 2017
  • #14
If a guy with an LS (yuk) in a stang can hang here then you'll likely be ok, even if you are a jeep person, after all jeep people are, well, strange.
But then, so am I. Strange that is.
 

imp

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Jul 13, 2017
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Sep 21, 2017
#15
  • Sep 21, 2017
  • #15
karthief said:
At the back of the upper intake, between the intake and the firewall there is a wade of wires with a black connector and a white connector, they are referred to 'salt and pepper shakers' because of that.
Click to expand...
Jeez, how much I learn of jargon to be added to the endless miasma of stuff already clogging my memory bank: bearing clearance tolerances, oil pan compatability, header clearances, allowable driveshaft run-out, engine dimensions, transmission swap overall lengths, rear rotor bracket accomodations, 9" Ford fitment to throw out GM crap, on and on, now I have to deal with the superfluous: salt & peppa.

Christ. I defer to you. imp
 

imp

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Jul 13, 2017
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#16
  • Sep 21, 2017
  • #16
karthief said:
If a guy with an LS (yuk) in a stang can hang here then you'll likely be ok, even if you are a jeep person, after all jeep people are, well, strange.
But then, so am I. Strange that is.
Click to expand...

Two quotes from the past, neither worth a sh!t:

"It's a Jeep thing".

"If it's not a Scout, it's just a Jeep".

imp
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,988
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polk county florida
Sep 21, 2017
#17
  • Sep 21, 2017
  • #17
imp said:
Jeez, how much I learn of jargon to be added to the endless miasma of stuff already clogging my memory bank: bearing clearance tolerances, oil pan compatability, header clearances, allowable driveshaft run-out, engine dimensions, transmission swap overall lengths, rear rotor bracket accomodations, 9" Ford fitment to throw out GM crap, on and on, now I have to deal with the superfluous: salt & peppa.

Christ. I defer to you. imp
Click to expand...
Take notes or use flash cards.
Thats what I do
Then I can't find the notes
 
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jrichker

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#18
  • Sep 22, 2017
  • #18
imp said:
Pardon my ignorance: What are "salt & pepper shakers" ? imp
Click to expand...

b]See the graphic for the 10 pin connector circuit layout.[/b]


The following are diagrams courtesy of Tmoss & Stang&2birds

Location of the TPS, IAB, and the 10-pin connectors on a 5.0, picture by TMoss:



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.



TFI module wiring for 94-95 Mustang GT
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-IgnitionControlModule.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

Complete computer, actuator & sensor wiring diagram for 88-90 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

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

O2 sensor wiring harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangO2Harness.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

Mustang 5.0 Lights and Radio schematic, by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxLights-Radio_diag.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

T5 Cutaway showing T5 internal parts
http://www.veryuseful.com/mustang/tech/engine/images/5_Speed_Cutaway_Illustrated.jpg

Visual comparison of the Ford Fuel Injectors, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/Ford_Injector_Guide.jpg

Convertible top motor wiring http://www.veryuseful.com/mustang/tech/engine/images/mustang88VertTopMotorCkt.gif

Engine mounted fuel injector harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangEngineHarness.gif

Location of the TPS, IAB, and the 10-pin connectors on a 5.0, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/TPS_IAB_Pic.jpg

Starter circuit
http://forums.stangnet.com/attachment.php?attachmentid=21328&d=1080916057

Alternator diagram for 94-95 Mustangs.
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-Alt.gif
 
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S

Spieg

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#19
  • Sep 22, 2017
  • #19
Thanks for the info jrichker. That will keep me busy reading for a while.
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
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Sep 24, 2017
#20
  • Sep 24, 2017
  • #20
4G-KDMP said:
This is the actual 10 pin extension

Click to expand...

no= those are the factory recall issued extenders for the salt and pepper connectors.
Toss them in the garbage
 
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