!990 dodge caravan transmission peculararity

[napcel]

When it gets cold out around 30 in the fall my transmission begins to shift erratically it did it last winter and it started again this year in the warm time of year it performs nicely without wierd shifting. Its a v6 3.0 L engine overdrive, drive, and low selections for the transmission. Ususally what happens is that it does a down shift into low gear when it should be at a higher posistion in the transmission and it could happen at speeds clear up to 40-45 mph. This is very uncomfortable and troublesome since I have to slow down and it wants to then stay in low gear till I stop or turn off the engine whatever. Sometimes does it and sometimes doesn't. Would a throttle posistion sensor do something like that, done some research but thought maybe someone could reflect to this and know what it was.

[jb been there]

Same problem on my '91 Caravan. New filter and fluid, but still no fix. Really will jar your teeth sometimes! This started happening suddenly with no warning. Has to be either a hydraulic peculiarity or electronic problem. My '93 Voyager will lock itself in 2nd and stay there until you stop and restart the engine. Obviously an electronic problem. Just started researching this. Hoping somebody else is ahead of me here!

[RIP]

Sounds like you're both going into what's called "Limp" mode. Your transmission electronics has detected a failure and is forcing you to slow down. There are many threads regarding this all over the forum. Early 90s vans use the OBD I diagostics system and I don't think there are fault codes for the transmission. Hope I'm wrong.

napcel - If it's been a while I would change the fluid and filter first. It's your cheapest move after getting the codes read.

Might gleen some info from this: http://www.allpar.com/fix/trans.html

[jb been there]

Just found some more info on this forum. Page 8 has a thread from thowell titled "if you are having the dam limp in mode problem Read this" and on p. 9 one titled "Everyone with Transmission problems ... A Chrysler secret ...! Read this...!."

Looks like several things to check out. There are input and output sensors, a ground cable, some faulty factory wiring, and a TPS that has an adjustable output voltage. Now, if I had any idea where any of those parts are.....!?

Hope you find yours. I'll see what I can do.

[napcel]

OK Rip,,,

First of all thanxxx for your interest. In my post.
Yea something is making it downshift ok thats for sure, but what makes me suspicious is the fact that it never does it till winter ever. 0 yes fluid has been changed put Lucas treatment in and all that. I was thinking with luck someone has had this identical problem and figured it out. I know if I do you will find the precise details of the event on my post. I am furious at this point about it also.
What upsets me the most is that they make this stuff prone to failure and thats the worse design features one could make and if thats all the better they are at making it they shouldn't be combinining this electronic componet crap in these vehicles. Or the other senario exists that they want to make us keep taking the flawed junk to their shops and keep pullin money outta us to bolster their enormous profit appetites. I'm about ready to get my old pick up outta the shed and drive around proudly in it at least it will run good old stuff we could work on.
Another thing about if they cared at all about the public would be that they would make all efforts to readily help people with all these symptoms and tell them probably what is wrong based on history, however they may have created to many side shows with all these little junctions and this little componet, anyways the only time this happens to me is in the winter other than that the stupid thing runs great any other time of the year.

Anyone can match this indentical problem I'd be grateful or any other input feel free to post away...............