Idling too high, esp in park

This just started today when I went to leave class to go to work. Needless to say the car is still parked where it was earlier... I have a 95 Lumina, it normally idles in park at around 500-1500 RPMs; however, today it shot up to 3000-3500 RPMs. It didn't go down while letting the car sit there, it just went up. When I put it in drive or reverse the rpms shot up and the car just about took off (I had to use the emergency brake as well as the pedal to stop it). Anyone have any ideas on what this might be before I get it towed to a mechanic?

Go to this thread.


http://www.automotiveforums.com/vbulletin/showthread.php?t=454660

Emissions controls will compensate for a vacuum leak with more fuel to balance out the combustion ratio.

Translation: Vacuum hose pops off, engine sucks air, ECM says "too much air, add more fuel".

Result: Idle way too high.

That was it, the vacuum hose to the master cylinder that had popped off. Thanks for the advice!