Mass air conversion using a9l on former aod car

[Mustang5L5]

Finally gonna convert my car to mass air. Figure I do it now so I can start on my h/c/I over the winter.

Car is a converted aod to 5 spd car running the aod computer and wiring.

I have a 5 spd a9l computer. Now, I plan on changing the o2 harness over to a 87-89 5 spd o2 harness to avoid that little issue.

Question is the trans harness. I have the aod trans harness which does notnhave the provision fpr the nss on top of the trans. I want to to avoid getting code 67s by not having it. Is there a way to jump this out on the computer? Ground a pin?

I actually tried trading the a9l fpr an a9p but got no takers

 

[NIKwoaC]

I actually tried trading the a9l fpr an a9p but got no takers

Eh, you don't want the auto ECM anyway. I've *heard* that they have different coding for decelerating and coasting that makes the engine act a little different when used in stick cars.

 

[Mustang5L5]

That is true. I remember reading about that as well. Kinda why I want to set everything as close to factory as a 5 spd came. Why I am changing the o2 harness out.

I jut don't want to pull the carpet up to run the trans harness just yet. Why I am trying to figure out how I can wire in an a9l using the harness which has no provision for the nss plug.

I've been studying my 1988 wiring diagrams and think I can ground pin 30 on the EEC....but not sure if that would cause any driving issues. Perhaps I can do that when I run the codes, but that's a pita.

I also want to make the cel functional

 

[Mustang5L5]

Well, found my answer. Temporarily grounding pin 30 will allow me to run the codes. So i'll install a jumper from pin#30 to chassis ground, with a toggle in between. Then when i want to dump codes, i'll close the switch and run them.

Then, next time i pull the carpet up, i'll replace the in-car trans harness to a 5-spd harness and do it correctly.

 

[jrichker]

Well, found my answer. Temporarily grounding pin 30 will allow me to run the codes. So i'll install a jumper from pin#30 to chassis ground, with a toggle in between. Then when i want to dump codes, i'll close the switch and run them.

Then, next time i pull the carpet up, i'll replace the in-car trans harness to a 5-spd harness and do it correctly.

That will work but...
If you dump the codes, don't forget to remove the test jumper and then drive the car. This could prove hazardous because test mode takes the throttle control away from the driver for several tests.

 

[ttopstang]

Eh, you don't want the auto ECM anyway. I've *heard* that they have different coding for decelerating and coasting that makes the engine act a little different when used in stick cars.

I heard the auto computer is what you want because it gives you better fuel curves.

 

['88 5FOX]

let me know how yours turns out. I will put mine back in and test away again. it only took about two hours following the instructions i found from all ford mustangs website. but it said nothing about changing o2 harness. I want mine to work for future upgrades. thx

 

[Mustang5L5]

Eh, you don't want the auto ECM anyway. I've *heard* that they have different coding for decelerating and coasting that makes the engine act a little different when used in stick cars.

You are right.

According to this, the AOD computer will not do fuel cutoff at under 6000RPM...which basically means it is turned off I assume. Looks like something is different in EGR programming as well

http://www.eecanalyzer.net/tech/docs/EEC_Compare.xls

 

[Mustang5L5]

That will work but...
If you dump the codes, don't forget to remove the test jumper and then drive the car. This could prove hazardous because test mode takes the throttle control away from the driver for several tests.

I'm usually good with remembering things like that.

Actually, i'll just use a blade fuse holder instead. When i want to dump codes, i'll stick a 5A fuse in and pull them...and then remove. That way a switch doesn't automatically get switched.


This is just temporary of course until i track down the correct trans harness and install it. I like things to work factory.