My daughter bought a 2000 Jetta GL and is having problems with the transmission not shifting at times. It will drive fine and then to get it to shift from 2nd to 3rd you have to run the RPMs up real high and pull off the gas then put it back to make it shift. Everytime she takes it to the dealer it won't do it. Are we dealing with a bad transmission or could it be something simple. We had some kind of chip replaced and it did fine for a little while but then started doing it again. Help!

Thanks so much for advice.

Mack