Engine computer

[PE1990]

Hi again. New question from a Mustang novise.

I am in the process of changing the original 5 speed with a auto transmission in my wifes 91 vert, (Pleeease don't ask me why).

Q:
1/. Do I also have to change the engine control computer?

2/. What will be the story if I keep the 5 speed computer?

3/. What is the cost of a new computer?

Regards, Per.

 

[txplayboy001]

What year is it?

 

[PE1990]

It is a 91 convertable GT

Per

 

[txplayboy001]

should not make a difference. Ford did not start electronic controled trannys until 93

 

[PE1990]

It is a 91 convertable GT

Per

 

[txplayboy001]

It is a 91 convertable GT

Per

You can keep your stock computer.

 

[88 Fox GT]

I do realize that the AOD is not electronically controlled, but I have been informed that you must have an computer (like an A9P) for an automatic tranny. Not sure how true this is or why it is, but it's what I have heard. Maybe someone else can give reasons as to why this is so.

 

[Funanin]

if the electronic controlled trannies didnt start till 93 then how does a twEECer work? How can u install a chip that changes the shift points and such on a 92 and earlier 5.0?

 

[HISSIN50]

one does need a puter for an automatic to run an automatic (it has tables and maps for the automatic features).

were one to go from an auto to a 5 sp, the auto computer can be used.

good luck Per - glad there are Stang enthusiasts in Lebanon too!

 

[PE1990]

Thanks


Thanks for advice. New computer will be installed today.

"glad there are Stang enthusiasts in Lebanon too!"

I believe Stang enthusiasts are all over the world.
Here in Lebanon I have seen all from 64 1/2 too 2004 models, however, GM are more plentyfull.
Have a 68 Buick Riviera myself, but just fall in love with that 91 Mustang GT convert.
Bought it for the wife, and therefore had to change the transmission.
The car is in the shop at the moment for a good check-up + the trans. Also a new "Ferrari Yellow" with Aluminium skirts paintjob and a new black top from "yearone".

Hopefully ready end of this week. As the weather is still good, a top down test drive is still possible.

Will probably soon be back with more questions, but let me just for now say:

All the best. Have a peacefull X-mas and a good new year to all of you.

Regards, Per.

 

[HISSIN50]

Thanks for advice. New computer will be installed today.

"glad there are Stang enthusiasts in Lebanon too!"

I believe Stang enthusiasts are all over the world.
Here in Lebanon I have seen all from 64 1/2 too 2004 models, however, GM are more plentyfull.
Have a 68 Buick Riviera myself, but just fall in love with that 91 Mustang GT convert.
Bought it for the wife, and therefore had to change the transmission.
The car is in the shop at the moment for a good check-up + the trans. Also a new "Ferrari Yellow" with Aluminium skirts paintjob and a new black top from "yearone".

Hopefully ready end of this week. As the weather is still good, a top down test drive is still possible.

Will probably soon be back with more questions, but let me just for now say:

All the best. Have a peacefull X-mas and a good new year to all of you.

Regards, Per.

That is pretty neat, Per. i've been some places, but your neck of the woods is not one of them; i would like to some day however.

my goodness, your vert sounds like a real beauty. post some pics if and when you can. yellow is a favorite of mine (as are GT verts).

We hope you have a wonderful Christmas and Holiday season as well!

 

[MatthewP]

Your A9L should run the car fine whether you have an AOD or a T5. I wouldn't bother changing it if I were you.

-Matthew

 

[txplayboy001]

92 and earlier ARE NOT CONTROLLED AT ALL BY THE COMPUTER! Line pressure controls the shift points. An AODE is contolled by the computer. That tranny is in 93 up. Detent cable and the trottle valve cable controls the AOD.

 

[1990Coupe]

The puters in the AOD and the t-5 are different.. i believe the differences are not only the mappings, but in the ignition retards... the t-5 retards between shifts, the and the aod (a9p) doesnt.. I just got done doing an AOD to 5 speed swap on a buddys car, we kept the stock AOD computer cause i thought it would be better.... but im not 100% sure, just my .02 worth...

 

[txplayboy001]

Well, I believe that the AOD comp has a better fuel map, not too sure though

 

[HISSIN50]

The puters in the AOD and the t-5 are different.. i believe the differences are not only the mappings, but in the ignition retards... the t-5 retards between shifts, the and the aod (a9p) doesnt.. I just got done doing an AOD to 5 speed swap on a buddys car, we kept the stock AOD computer cause i thought it would be better.... but im not 100% sure, just my .02 worth...

this is my understanding as well. AOD puter works in a 5 sp swap (great, if not better than the 5 spd puter), but stick puters dont like being run in a car coverted from a stick to an auto.

ive got a link around with all the specifics, but i cant find it.

 

[88 Fox GT]

That's what I have heard as well. Timing retards and advanced along with fuel curves are supposed to be better in the A9P (automatic) computer. It's supposed to work better with the auto tranny.

The auto would function alright with the 5-speed computer, just not to it's optimum performance with the engine.

Hell, there are people putting AODs in classic Mustangs and they don't have a computer at all, so it probably would function alright.