Transmission problem but is not in limp mode.

[fatness_42]

Ok the tranny is shifting weird. It is not in limp mode. If you put it in drive you can feel it go in to gear. But when you take your foot off the brake and try to give it gas it's like it goes to N. like a slip would do. But the weird thing is if I put it into 1st it goes fine than I can shift to second and 3rd. Then when I come to a stop I have to shift back into 1st. Obviously I haven't drivin it like this very much just a couple of blocks and in the parking lot trying to get a feel for what it is doing. If the tranny was messed up it gave me no previos warning other than this. It awalys shifted solid and quick. I tried to pull codes from the TCU and it didn't give me anything not even the good all cear no signal at all. I checked the TCU fuse and its fine. I decided to pull it out at look at it to see if the caps had leaked. And to my suprise it is a TCU for a 91-92 FWD and mine is AWD. Should I assume that the TCU is bad? does anyone know if the FWD and AWD in 91-92 are compatible? Does anyone know where I can get one rebuilt it is an Eprom that I would like to be able to keep if I can get it fixed or if it does not work for an AWD i'll get it fixed and sell it so that I can buy one that will work for my car. I haven't had the car very long but it seemed to shift fine till now so I'm guessing that it is compatible. The fluid is not burnt at all and it's full too. Just don't know what to think at this point. All I know is if it's anything other than a TCU the car will be a 5 speed when I'm done. Thanks for any help. The car is a 91 AWD Talon.

 

[fatness_42]

Today I pulled the fuse on TCU and the car went into limp mode. So i'm pretty sure it is the TCU. I just wanted to be sure before I spent 100 or so on one. I am starting to wonder if there may be something wrong in the cars wiring though. The guy that had the car before me bought it with the tranny messing up so he changed it. Which did not fix the problem so he put in 2 TCU's and finally it fixed the problem one of which is the one that I am now having a problem with. They were both used TCU not rebuilt ones I would imagne it's just because they mess up all the time though. CRAPPY CAPS!

 

[rbwtrans]

Caps are a BIG problem with the old TCU's. They cause acid damage to the board much like the ECU's do. They usually attack the shift solenoid and/or the speed sensor traces as well. As far as I know, the only difference is the chip between the 2WD turbo and the AWD. It's just a little bit of difference in the shift scheduling to compensate for the extra drivetrain (a little bit longer shifts in the AWD). As far as getting yours rebuilt, Steve rebuilt mine a few years ago. At that time, he said that it was the first TCU that he had done. I don't know if he's done anymore, but I've never had another problem with mine since he fixed it. (Steve's the MAN!) Good luck with your car and I hope that you can get your issue(s) resolved.

 

[fatness_42]

Well I bought a FWD TCU and the problem remained. I do not believe that the TCU is bad I would have to throw it in a FWD to find out for sure I would imagne. But it looks clean, clean board looks excellent and it gave me good strong pulses when I checked it for codes. But I say do not use a FWD in an AWD. I came to find out that the car had one in it from the day I bought it. When it started acting up I bought one from a guy on here like I said I believe it to be good. I also got an AWD one tonight refubished from Advanced auto and bam fixed. I am going to see what I can do with the extra one I have to make sure it's good so I can sell it. It lookes to also be a refurbished. The one that was in the car I know was bad the cap had leaked on to the board and when I checked it for codes it gave me the all clear but the pules were very low so low you could barley see the needle move on the ohm meter even turned all the way down to 5 volts. I turned it in for the core. Ha advanced auto got the wrong core hell they didn't notice. Maybe they don't care? Thanks for the help to everyone that replied.