Originally Posted by Doru

Above my 1-2 hard shift fix.
I know about that rubber seal, the thing is that lots of the time the battery can get low voltage, corrupting the car's modules. And sometime you cannot even connect to it. I just re-flashed the latest tranny software and this fixed the annoying 1-2 jerk when cold. I would try this first, before dropping the mechatronic unit. If this doesn't do it, then it could be the bridge seal, or low ATF, or clogged filter. Fmugur can chime in, he was there.

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