1993 Mercury Cougar idle waaaaaay too high

I have had this cougar for five years now and she has been a great car until three weeks ago. I was driving to work and all of a sudden it began accelerating on its own. I could hardly get it to stop so I popped it into neutral. The motor then revved up to almost 3000 rpms. I have no cel or studdering or any other mechanical issues to speak of just high revving. I have replaced tps maf and the egr valve nothing has helped. This issue is making it dangerous to drive and is wearing the brakes excessively. Alot of the time I can smell the brakes burning when stopping at lights. Plz help me.