MX-3.com

Ok so i have a 92 gs auto tranny, and im sure the first thing yall are going to say is do a manual swap, but im not at the point yet.
the tranny still pulls hard all the way through first but never seems to shift to any other gear...so i took it to a shop and they recommended that i have the ecm remanufactured. so i called some ecm repair places i found over the web and they told me this was very popular problem with the mx3 and that i should have the ecm looked at. i decided to take the cheap way and just buy a used ecm over ebay hopping that would fix the problem. well i got the ecm in today and plugged it in but it will still not shift. my question is do i have to do anything to reset the car in order for the car to recognize the new ecm? or should it just be a simple swap, or will replacing the ecm even fix this problem?

The reason that there is practically no information on here about auto trannies is because there are practically no auto tranny owners that keep them and or do any work on them. Your best bet woul dbe to ask the ecm guy that told you it needed work the same question you asked here. He woul dknow better than 99% of us.

ok correct me if im wrong, but the tranny computer and the ecu/ecm are all one unit correct?

idontknow wrote:ok correct me if im wrong, but the tranny computer and the ecu/ecm are all one unit correct?

You're wrong.

What he means to say is, that the auto tranny has a separate ECU which is located under the passenger's seat (I think). there is a section on the auto tranny in the manual. You can probably learn a lot from that.

http://www.mx-3.com/manuals/index.php?f ... 0Manual/K/" onclick="window.open(this.href);return false;

ok this was really helpful, thanks guys!!!!

Passenger seat has the ABS

think i found it. i think its the computer under the radio

idontknow wrote:think i found it. i think its the computer under the radio

Yep... that's the one. Directly under the radio, not the one towards the passenger side firewall. Although, before replacing anymore computers, I'd disconnect the battery and hold the brake pedal down for a bit to discharge capacitors. Then go for a drive. Sometimes those computers just need to be reset, seen it before...

I would first check to see if the car will start in gears other than P and N, usually when the car will not shift past first its not reading the signals from the transmission and has gone into limp mode. If there was no slipping prior to the failure then there is a 90% chance that the problem is electrical. I have had several of the neutral safety switch failures mimic a transmission failure. All the wiring for the shift solenoids and valve body in general are routed through that switch, because the switch wiring moved internally contacts wear out hence the loss in signal. If the car starts in any gear other than P or N then its that switch that is shot not the transmission. As an added fyi the biggest single source of these transmissions failing was the cooler, they had a very poor cooler from factory it is just a single metal pipe with no cooling fins to speak of, overheated oil attributed to the auto trans clutch packs prematurely wearing out and clogs in the valve body. Adding an aftermarket cooler with an inline filter can reduce this problem by as much as 85%. I have personally torn apart these transmissions and have rebuilt them, 1 was put into a turbo mx-3 with a bpt swap and his transmission has held with no problems to date (over a year now, the guy hates stick shift) I added an aftermarket cooler and a hydraulic filter that is 10 micron absolute, it still shifts like new with 0 problems to date. Yes he does drive it hard on occasion but he changes that filter every year and he keeps an eye on the colour and condition of the fluid, changing it every 50,000 kms religously.

Wow.. i did not know that. I also have trouble with my 92 GS automatic.
It has a long hard shift into 2nd gear. All others shift fine unless car acts up,
then i have trouble with first as well.

Check the condition of the transmission oil, it should be bright red and also check the level, it needs to be at the full mark fully warmed up and idling. If its a dark red or browm then get it changed asap to save the clutch packs.

umcamara wrote:Yep... that's the one. Directly under the radio, not the one towards the passenger side firewall. Although, before replacing anymore computers, I'd disconnect the battery and hold the brake pedal down for a bit to discharge capacitors. Then go for a drive. Sometimes those computers just need to be reset, seen it before...

i gave this a try and it didnt work, but thanks for the help

Newfie_dan wrote:I would first check to see if the car will start in gears other than P and N, usually when the car will not shift past first its not reading the signals from the transmission and has gone into limp mode. If there was no slipping prior to the failure then there is a 90% chance that the problem is electrical. I have had several of the neutral safety switch failures mimic a transmission failure. All the wiring for the shift solenoids and valve body in general are routed through that switch, because the switch wiring moved internally contacts wear out hence the loss in signal. If the car starts in any gear other than P or N then its that switch that is shot not the transmission. As an added fyi the biggest single source of these transmissions failing was the cooler, they had a very poor cooler from factory it is just a single metal pipe with no cooling fins to speak of, overheated oil attributed to the auto trans clutch packs prematurely wearing out and clogs in the valve body. Adding an aftermarket cooler with an inline filter can reduce this problem by as much as 85%. I have personally torn apart these transmissions and have rebuilt them, 1 was put into a turbo mx-3 with a bpt swap and his transmission has held with no problems to date (over a year now, the guy hates stick shift) I added an aftermarket cooler and a hydraulic filter that is 10 micron absolute, it still shifts like new with 0 problems to date. Yes he does drive it hard on occasion but he changes that filter every year and he keeps an eye on the colour and condition of the fluid, changing it every 50,000 kms religously.

yep the car only starts in neutral and park

Newfie_dan wrote:Check the condition of the transmission oil, it should be bright red and also check the level, it needs to be at the full mark fully warmed up and idling. If its a dark red or browm then get it changed asap to save the clutch packs.

had the tranny oil replaced today; still not shifting...

so im almost positive that it is the tranny computer at this point

out of curiosity does the hold light on your dash come on at all?

my hold light on dash comes on when my car dies and one time when it didnt die but tried to and then the car acted like it didnt know if it was in gear or not.