2001 Chevy Cavalier Engine revving while driving

Our Cavalier has an annoying habit of revving up from roughly 2000-3000 rpm, usually when travelling at 50-100 kph. Sometimes it will rev and drop back right away, sometimes it will rev up and down 2-3 times in a row and sometimes rev up and hold it there for a few seconds. To me it seems like it wants to change to the next gear up but "can't decide" what it wants to do. Usually this will appear for a week or two, and then go away for awhile. Dealer thinks it is some valve that is sticky. Sorry, I can't remember exactly what valve he mentioned.

And to top it off, today the brake lights refused to turn off, even when the car is off. I had to pull the fuse to get them to go out. The switch on the brake pedal seems to move freely but is a little loose in its mounting bracket.

Any help/ideas would be fantastic!