My 94 cuttless ciera is going 5mph up to 30 mph without me giving it gas. Sometimes when I park & shut it off it's idle is so high it sounds like the engin would blow right out from under the hood?
Could be a stuck throttle body. Go to parts store, and buy some throttle body cleaner. If that doesn' t do the trick, UR gonna need a mechanic.
That sounds like the IAC is operating erratically, you can try taking it out and cleaning it but if it has never been changed it most likely needs replacing.