I have recently purchased a 1995 850 T5 with 100k miles. It is exhibiting two commonly reported problems (possibly related).

1. Cold weather transmission shift stick.
2. Intermittent failure to start.

I have read two solutions, which are to Replace the PNP Switch or to Replace the Tranny Fluid. Most of these posts have described error codes/lights. None of my fault codes seem to do with the transmission.
(A3 142; B1 132, 134, 235, 414; B2 122).

My question is with either of the aforementioned problems/fixes will you always get fault codes? Which would you suggest to do first or should I just do both? A longer description of my experience follows:

The car starts fine on the first start of the day. If I go for a short distance and turn it off, it will not start back for a few moments. During this wait, I have changed gears, opened and shut the door, taken the key completely out, and did a hula dance (not really) without seeing one thing that definitively fixed the problem. When first driving, it will rev high in low gear until it gets a little warm. Also one day @ 60 mph, after beginning in a lower gear, it did shift back and forth between gears a few times before settling into high gear. This morning, I started the car and let it warm up for about 30 minutes, and it shifted fine from the start.