2001 Saturn SL2 Car hot, fans on, car acts like it is neutr

The other day I was driving my Saturn (as usual) fans running, air conditioning on, loss of power (typical) and then all of a sudden my rpm's increased and my car was only on average going 30mph. It was like I had accidentally shifted into neutral.

I made it back to work and in about 45 mins I headed home (estimated 15-20 miles) the car drove fine (no ac on) and by the time I got home the same scenario as above happened. This time, I had to pull over, shut my car off and restart it to make it the rest of the way home.

Currently, my car is waiting to be worked on at a transmission shop. I read previous car questions on your site and it sounds like other people have had this same problem. Something with TPS? Any help would be much appreciated so that I don't waste a ton of money at the transmission repair shop.

Oh, and when I run my ac and am at a stop I have to hold my foot on the brake (hard) so that my car doesn't lurch forward.

Thank you,
A Flaherty