1990 C2 Tiptronic acting "funny"

burked · 03-30-2013, 02:35 PM

Hi All,
After a long winter rest, I took my car out for the first time today. The transmission, when in manual mode, worked as usual. When in automatic mode, it acts odd. From a stop, it seems fine, though the 3-4 upshift is at about 42 MPH
which seems high (very light acceleration). I feel it downshift 4-3 about 38 MPH, can't say whether or not I ever noticed that before.

The odd thing is that if I start from manual mode, get up to speed (like an onramp) then switch to automatic at about 50 MPH, the car downshifts to 3rd and stays there. If I start off and switch to automatic mode under 40, it stays in 4th until around 50 or so, then downshifts to 3rd.

I've looked at my books and "googled" - nothing similar that I've found.

For history, I've had the car about 7 years and 70,000 miles and never a peep out of it - it has been flawless. I'm assuming that if there were a diagnostic, I'd see the "!" light come on. Maybe I'm mistaken.

I'm open to any suggestions!?!?!
Thanks!
-Dave

mike monde · 04-01-2013, 01:12 PM

You may want to post this question over on Rennlist as there is a more active 964 board. I own a TIP and have not had this problem but I would be interested to see if anyone has a thought on it...good luck...

burked · 04-07-2013, 12:25 PM

Hi - thanks for the advise - I did play with the connections to the module under the drivers seat - it appears to be in there, as it cleared up but returned a bit later.

If it ever gets "warm" again, I'll to a thorough contact cleaning.

Thanks again
Dave

cjoenck · 04-10-2013, 08:02 AM

Maybe too obvious, but when was the last time you looked at the ATF level and / or changed it?
Did you disconnect the battery by any chance during winter storage? The TIP is adaptive and will "learn" based on your driving habits. If disconnected for a long time, it will forget stored parameters.

Just a thought.