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Rednotch:

If you feel like doing a little more investigating, could you check the ECU harness of each of those, and get wire colours that are getting turned around in there? That would be a help, eliminating more guess work.
I've got a mix-matched setup going into my ride as well.
 

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Mine is an '88 manual, SD in a '97 Ranger. This application does not use the transmission neutral connector, so to avoid code 67, I keep my foot on the clutch while checking codes (I does have the Clutch Pedal Position switch functioning properly)

This may help someone else.

I do have an ECU form a '92 Mark VII LSC, which is Speed Density also, and from an auto. I'm not able to check any codes while using this ECU.
 

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The SD cars had no VSS signal at the ECU, they would be pins 3, and 6, if present (like a MAF car). I do have an ECU from a '92 Mark VII LSC (5.0 HO) which is Speed Density, and also has a pin 3 and pin 6 (for the cruise)

Post 83, connector 40, shows "NDS Pin 30" (nuetral drive switch). On a manual car, this was titled "clutch/nuetral gear switches" in my reference material.

Still in post 83, connector 40, the "auto" and "manual" circuits refer to pin 46, signal return. This is where the O2-end of that connector differs. On "manaul" cars, pin30 comes out of the O2-harness end of that connector, and loops to "manual". On auto cars, pin 30 loops to "auto" at the same point.

As we've established early in this thread, and in the real world, the physical location on the connector, and the wire colour, differs with the year, and/or trans type. It can be different from that picture (connector 40).

Pins 30 and 46 are the two circuits that are connected by the clutch position switch, and/or/nuetral switch(es) on the transmission to allow starting.

Here's an '88 pinout, notice under "Mustang", it lists TWO SEPERATE names and wire colours for pin 30:



Also, www.fordfuelinjection has a ton of colourful diagrams for various years, as well as scans of actual EVTMs:
http://fordfuelinjection.com/?p=37
 

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i got a 87 gt 5.0 aod and plan on swapping to a 5 spd. can i use the same computer and o2 harness? do i still gota get the 5 spd tranny wiring ?

i also got factory 88 5.0L 5 spd wiring and computer when i switched my 88 to 93 stuff for mass air.
so what would be better to use?
Swap only the trans harness, and you'll be fine.

I didn't need a Mustang trans harness for my rig, are the connections different for aod and T5 trans harness'? (the neutral switch)
 

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The self test input is ECU pin 48.
So, you can check at the (ecu)connector for colour.

For 1988 it was T/R for Mustang(other models were different), later MAF cars I'm showing White/Red.

Just checked the EVTMs shown on fordfuelinjection.com , 1987 was also tan/red for the STI
 

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I guess that leads me to my next question...the trans harness with regard to the nss on the trans an pin 30. I still have the aod trans harness which does not have the nss wiring. Now, until I locate and swap in the right harness, what problems can I expect? I imagine it would generate a permanent code 67 unless I ground pin #30 to the chassis and then run codes

Is this safe in terms of how the car runs? Would not having a nss hooked up on the trans cause any driveability issues. I assume when not running the codes, I should unground pin 30 during normal driving


I know I'll have to repin some stuff and add three wires for the maf conversion, but if I can round up the trans harness before then, I'll just swap the two harnesses (or repin the jumper in the o2) and call it a day
A manual car is wired like this, the trans switch a clutch pedal switch are in parallel, so if either clutch is pressed, or trans in neutral, it get connects 46/30 and eliminates code 67 and any idle issues.


I wired my neutral switch together at the clutch pedal (this is not the same wires as the start interrupt) as I have no trans wiring in my application (Ranger). Leaving this connected full time creates no driveabilty issues.
 

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So in the meantime What's the best way to wire if you do a 5spd swap, swap to a 5 spd eec and won't be able to hook up the nss on top of the t5?

Need to do anything? Or not? It's wired in parallel with the clutch nss right? So pressing the clutch in will clear cpde 67 and allow me to dump codes right? Will not having the trans nss hooked up cause any driveability issues?
Yes, as I said, I have no wiring for a trans neutral switch, I jumped those two circuits at the pedal switch, full time. This improves idle quality. (67)
 

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After building an all new harness for my truck, it occurred to me...

Use whichever O2 harness you like, and simply splice the two appropriate circuits together on the engine harness side of the O2 connector. Simplifies things a great deal!
 
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