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

Putting factory F I back on

  • Thread starter Thread starter snakin
  • Start date Start date May 1, 2022
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snakin

20+ Year Stangneter
Mar 24, 2002
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#1
  • May 1, 2022
  • #1
I'm looking at a Coupe that is carbed. Can I get a factory F I setup and a computer with wiring harness , MAF and switch it back?
 

2000xp8

SN Certified Technician
Aug 8, 2003
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#2
  • May 1, 2022
  • #2
People convert cars different ways.
If it's not chopped up, could be almost plug and play.
If it's hacked, could be trouble.
You can also consider doing a standalone system.
To be clear, i'm not the guy that pushes tuning or aftermarket systems on everyone, but if it's all missing already...
 

General karthief

wonder how much it would cost to ship you a pair
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#3
  • May 1, 2022
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What year?
And I agree with the aftermarket efi, like stated, depends on year and how 'hacked' the wiring is now.
 

bird_dog0347

still married haven't seen testicles in years
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#4
  • May 1, 2022
  • #4
Agreed, if the wiring isn't all there or was hacked up it might be easier and cheaper to get the Holley system that replaces the carb so you don't have to get a new intake as well.
 

Mustang5L5

That is…until I whipped out my Bissell
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#5
  • May 1, 2022
  • #5
It’s possible. How difficult it will be depends on how hacked the harness is as stated. These harnesses are year specific.
 

snakin

20+ Year Stangneter
Mar 24, 2002
30
16
18
NC
May 1, 2022
#6
  • May 1, 2022
  • #6
It's a 91 but the harness is hacked soooooo. Thanks guys
 

Mustang5L5

That is…until I whipped out my Bissell
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#7
  • May 1, 2022
  • #7
1991 engine harness is 1-year only. You’ll need to find that exact harness of you want to use factory EFI
 
M

Monkeybutt2000

Mustang Master
Aug 11, 2019
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#8
  • May 1, 2022
  • #8
snakin said:
It's a 91 but the harness is hacked soooooo. Thanks guys
Click to expand...
I don't understand why people do this.It's very simple to just remove the harness. In this case, Holley termi X is your best bet.
 

manicmechanic007

5 Year Member
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#9
  • May 2, 2022
  • #9
It should be easy to find a 91 harness?
 

evintho

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#10
  • May 2, 2022
  • #10

1991 Ford Mustang 5.0 302 foxbody Mass Air Engine Wiring Harness | eBay

Find many great new & used options and get the best deals for 1991 Ford Mustang 5.0 302 foxbody Mass Air Engine Wiring Harness at the best online prices at eBay! Free shipping for many products!
www.ebay.com
 
M

Monkeybutt2000

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#11
  • May 2, 2022
  • #11
evintho said:

1991 Ford Mustang 5.0 302 foxbody Mass Air Engine Wiring Harness | eBay

Find many great new & used options and get the best deals for 1991 Ford Mustang 5.0 302 foxbody Mass Air Engine Wiring Harness at the best online prices at eBay! Free shipping for many products!
www.ebay.com
Click to expand...
That doesn't even include the injector harness. Not to mention no ECU.
 

manicmechanic007

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#12
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A wrecking yard is where to find a complete harness
 

General karthief

wonder how much it would cost to ship you a pair
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#13
  • May 2, 2022
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manicmechanic007 said:
A wrecking yard is where to find a complete harness
Click to expand...
Dude, a fox mustang in a 'bone yard' is as common a chicken lips.
 
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Monkeybutt2000

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#14
  • May 2, 2022
  • #14
manicmechanic007 said:
A wrecking yard is where to find a complete harness
Click to expand...
Finding a 5.0 Fox in a wrecking yard nowadays is like seeing Bigfoot. The Holley is a no brainer in this situation IMO.
 
Reactions: Gs1987GT

manicmechanic007

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#15
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I have Holleys on three cars myself
They are great
Until you try to get it started in January
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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May 2, 2022
#16
  • May 2, 2022
  • #16
I’ve heard positive things about this kit, but I do think if the car is near stock, a good condition oem harness and ECU might be the way to go.

https://www.summitracing.com/parts/hly-550-937f?seid=srese1&gclid=EAIaIQobChMIzcetw5rC9wIVhAaICR3OfwlDEAQYASABEgICJPD_BwE

But harder and harder to find good condition 30 year old harnesses and ECUs
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,923
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#17
  • May 2, 2022
  • #17
manicmechanic007 said:
I have Holleys on three cars myself
They are great
Until you try to get it started in January
Click to expand...
Holley EFI not a Holley carb.
 

manicmechanic007

5 Year Member
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#18
  • May 3, 2022
  • #18
So you put Holley EFI on it and it breaks down in 15 years
Who supports or is gonna fix it? You?
If it hits the dealer or a reputable shop they will want to start over at that point
Might just as well go factory right now and skip the aftermarket
25 years ago when the holly efi came out they were turds
I realize they are much better now but they are still not for me
It's like having aftermarket cruise on your car
If anything happens you need a whole new kit because individual parts are not available
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,923
10,569
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polk county florida
May 3, 2022
#19
  • May 3, 2022
  • #19
manicmechanic007 said:
So you put Holley EFI on it and it breaks down in 15 years
Who supports or is gonna fix it? You?
If it hits the dealer or a reputable shop they will want to start over at that point
Might just as well go factory right now and skip the aftermarket
25 years ago when the holly efi came out they were turds
I realize they are much better now but they are still not for me
It's like having aftermarket cruise on your car
If anything happens you need a whole new kit because individual parts are not available
Click to expand...
Who cares what happens in 15 years, society feeds on instant gratification,
 

manicmechanic007

5 Year Member
Sep 26, 2017
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May 4, 2022
#20
  • May 4, 2022
  • #20
I should be quiet
I have not even seen my Mustang for 2 years or so
It sat for 35 years before I got it out this last time
But it ran. Just new fuel and a battery and some air in the tires I drove it away
 
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