I have a big issue with my engine over revving. the clutch will not drop the rps, the car acts like its an automatic without using the gas pedal, like its driving itself, this usually happens if i've been driving for about an hour and a half. turn the car off for twenty min usually fixes the issue. If I use the a/c the problem happens right away.

check your throttle body make sure its not sticking but is sounds like one of your sencors on the trottle body is messed up if you have a haynes it tells you how to check them