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Electrical what speed sensor eletrical wire is for?

  • Thread starter Thread starter Jean-Marie GT
  • Start date Start date May 11, 2022
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    electrical connection fox body speed sensor t5 transmission vss
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
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May 12, 2022
#21
  • May 12, 2022
  • #21
DA1 computer.

That’s a 1987 5-speed speed density ECU
 
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Jean-Marie GT

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#22
  • May 12, 2022
  • #22
Wow really . They put a 87 ecu in a 89 or its not a real 89
 

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General karthief

wonder how much it would cost to ship you a pair
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#23
  • May 12, 2022
  • #23
Put the vin number into this

1979-93 Capri and Mustang Decoder

foxchassis.com
 
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Jean-Marie GT

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#24
  • May 12, 2022
  • #24
That said 1989.
 
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Jean-Marie GT

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#25
  • May 12, 2022
  • #25
Do you know if its the ecu plug is the same for 87 and 89
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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May 12, 2022
#26
  • May 12, 2022
  • #26
It is. You’ll need to dig deeper.

Is the MAP sensor on the firewall connected to manifold vacuum or sampling atmospheric pressure?
 
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Jean-Marie GT

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#27
  • May 14, 2022
  • #27
the map is connected to the intake
 
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Jean-Marie GT

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#28
  • May 14, 2022
  • #28
There is a hose from the map to the air intake
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
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May 15, 2022
#29
  • May 15, 2022
  • #29
So it’s entirely possible your ‘89 has been swapped to a speed density setup.

To answer your initial question, the VSS is not used at all with speed density other than with cruise control.

As to why the car has been swapped, someone probably did some hackery in the past maybe using a donor 87-88 and a roller 1989. Wouldn’t surprise me
 
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Jean-Marie GT

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#30
  • May 15, 2022
  • #30
Thanks now i understand why the wire is Cut.
What are the + and the - of a speed density vs maf
 

KRUISR

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#31
  • May 15, 2022
  • #31
On your VIN, the 5th to 7th digits are P4x, what number is the x?

After those three there is a letter, what is it? If it is an E the car was born with a 5.0, if it is an A then you have a 4 cylinder car someone did a 5.0 speed density swap.
 
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Jean-Marie GT

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#32
  • May 15, 2022
  • #32
Its a E
 
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Jean-Marie GT

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#33
  • May 15, 2022
  • #33
Why somebody would swap for a speed density?
What is the advantage?
Somebody told me i cant instal Cam if i dont have a maf
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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#34
  • May 15, 2022
  • #34
No real reason to purposely do it.

In stock form the speed density cars run a bit stronger, however they are very sensitive to vacuum leaks and your hands are tied when it comes to cam swaps.

You could easily convert to mass air. Here are harness kits available
 
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Jean-Marie GT

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#35
  • May 15, 2022
  • #35
I think There is already the maf plug. I Will take a look later
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,180
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May 15, 2022
#36
  • May 15, 2022
  • #36
You are really going to need to roll up your sleeves and take a look at how this is wired to see if it’s done correctly.
 
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Jean-Marie GT

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#37
  • May 15, 2022
  • #37
Instead of Harness. I Will need a ecu if i swap to maf
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,180
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May 15, 2022
#38
  • May 15, 2022
  • #38
Jean-Marie GT said:
Instead of Harness. I Will need a ecu if i swap to maf
Click to expand...

You will need to do some minor requiring of the harness.
 
J

Jean-Marie GT

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#39
  • May 15, 2022
  • #39
Except the Maf sensor plus . What is the différence between maf Harness and speed density
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,180
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May 16, 2022
#40
  • May 16, 2022
  • #40
That's a broad question to answer. Ford made small changes in the harnesses year by year so that they don't really interchange with each other. It's not a speed density harness vs mass air, but rather 1990 harness, 1991 harness, etc.

Some of the individual wires route differently. For the most part if you want to swap to mass air you'll need a conversion harness, and also pay attention to the O2 sensor jumper pinout
 
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