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Electrical I need a new engine wiring harness. Recommendations please.

  • Thread starter Thread starter evintho
  • Start date Start date Dec 9, 2023

evintho

20+ Year Stangneter
Nov 12, 2003
683
245
73
Santa Rosa, CA.
Dec 9, 2023
#1
  • Dec 9, 2023
  • #1
OK, the snowflakes are a bit much. Pretty distracting!

With that being said.......I need to replace the entire ECU wiring harness. '93 5.0. The 30 year old original just isn't cutting it! I need to replace virtually every wire and connector off the 60 pin connector. Painless is quality and I found this over at Summit but it just doesn't look like everything is there. For instance, I don't see any connectors for the two 10 pin connectors, and those are crucial. I don't need any EGR or TAD/TAB connectors as those components have been deleted. Also, I believe the O2 harness is separate.
Is this what I need? What about a 10 pin harness?? Any help is appreciated!
https://www.summitracing.com/parts/prf-60510?srsltid=AfmBOorr5PZ4VJ8SF2f_Vs_Em8YVra1KZ_I_5ggDCRO9m5cg-SC2KPCr_pE
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,865
10,536
203
polk county florida
Dec 10, 2023
#2
  • Dec 10, 2023
  • #2
So you can see the floating dots too? I thought I'd dropped my kindle once too many times
 

Mcmahst

5 Year Member
Jan 19, 2021
666
261
83
Laguna Woods CA, fort Mohave AZ
Dec 10, 2023
#3
  • Dec 10, 2023
  • #3
I believe that harness eliminated the two salt pepper shaker connectors. If you look closely, there are 4 fuel injector plugs on the two sub harnesses off the main. Have you considered a good used harness? They are out there.
 

evintho

20+ Year Stangneter
Nov 12, 2003
683
245
73
Santa Rosa, CA.
Dec 10, 2023
#4
  • Dec 10, 2023
  • #4
Yeah, I really don't want to replace a 30 year old harness with another 30 year old harness. Does anyone make a new replacement harness?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,807
3,941
183
Claremore, OK
Dec 10, 2023
#5
  • Dec 10, 2023
  • #5
Nope. I had two brand new Motorsport harnesses that were based off the 93 cars and the only thing they lack are the air bag wiring which is easy to swap in. I sold one and am keeping the other one for my Coupe. They pop up from time to time on eBay and what you are looking for is the Ford Motorsport M-12071-C302 wiring harness.
 

evintho

20+ Year Stangneter
Nov 12, 2003
683
245
73
Santa Rosa, CA.
Dec 10, 2023
#6
  • Dec 10, 2023
  • #6
Is this the beast in question?

NOS M-12071-C302 Ford Motorsport Engine Wiring Harness 5.0 EFI V8 5.8 Foxbody | eBay

<p>NOS Ford Mustang Wiring Harness 5.0 EFI M-12071-C302</p><p>These harnesses were Fords official offering to those looking to mass air swap a 302 or 351w engine in to virtually anything. Since this exact harness is the same as the 92-93 mustang harness it has the fuel pump relay on the ECU...
www.ebay.com
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
Apr 3, 2009
2,981
1,622
153
nevada
Dec 10, 2023
#7
  • Dec 10, 2023
  • #7
That's a nice one but jezzz 700 ouch!
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,807
3,941
183
Claremore, OK
Dec 10, 2023
#8
  • Dec 10, 2023
  • #8
That is the one. Unless you are dead set on using the factory 60 pin connector for a processor that plugs directly into it then you may want to look at the Pro-M setup as they can wire the harness that comes with it to plug into your year of car. I believe there is a company that does this with the Holley Terminator X as well.
 
Reactions: Mcmahst

weendoggy

5 Year Member
Jan 14, 2019
198
57
38
Aptos, CA
Jan 1, 2024
#9
  • Jan 1, 2024
  • #9
evintho said:
OK, the snowflakes are a bit much. Pretty distracting!

With that being said.......I need to replace the entire ECU wiring harness. '93 5.0. The 30 year old original just isn't cutting it! I need to replace virtually every wire and connector off the 60 pin connector. Painless is quality and I found this over at Summit but it just doesn't look like everything is there. For instance, I don't see any connectors for the two 10 pin connectors, and those are crucial. I don't need any EGR or TAD/TAB connectors as those components have been deleted. Also, I believe the O2 harness is separate.
Is this what I need? What about a 10 pin harness?? Any help is appreciated!
https://www.summitracing.com/parts/prf-60510?srsltid=AfmBOorr5PZ4VJ8SF2f_Vs_Em8YVra1KZ_I_5ggDCRO9m5cg-SC2KPCr_pE
Click to expand...
That harness is what you need. I've done two of these in the past and are working fine. You eliminate all the stock Ford crap, so unless your going to change the ECU, it'll work. Going with another type EFI system will cost you a lot more.
 

evintho

20+ Year Stangneter
Nov 12, 2003
683
245
73
Santa Rosa, CA.
Apr 7, 2024
#10
  • Apr 7, 2024
  • #10
Just bringing this back from 4 months ago.
UPDATE:
I installed the Painless harness from Summit and all is right in the world! The car starts immediately, idles perfectly and runs smoothly. That 30 year old harness was definitely the problem! The Painless harness does away with the salt & pepper shakers, TAB & TAD connections and a few other unnecessary wires. It does retain the EGR connections though. It includes a new injector harness also. The only piece I had to reuse was the O2 harness. All in all, I'm very satisfied!
 
Reactions: Mcmahst, weendoggy and General karthief

Mcmahst

5 Year Member
Jan 19, 2021
666
261
83
Laguna Woods CA, fort Mohave AZ
Apr 8, 2024
#11
  • Apr 8, 2024
  • #11
Congratulations on finding your solution.
 
Reactions: limp
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