i own a 99.5 VW jetta 5 sp manual. in december (very cold temps here) i noticed a problem shifting into fifth. 2-3 days later i found that i couldn’t find reverse or first, it was either one or the other. after input from mechanic friends i did not drive the car. it is now august and i took it for a drive the other day. to my surprise these problems were nearly gone. i feel a slight resistance when shifting into first and fifth, and that seems to be it. does anyone have any insight as to what the problem might be?
You need to find a good independent VW mechanic (use the Car Talk mechanic finder) and have them take a look. It could be a number of things, some easy to fix (adjustment, lubrication of the linkage, low oil (find the leak if so)), some much more expensive (clutch issues, something internal to the transmission). Good luck!