my car will cut out while driving in all gears at all rpms

Question: I have a 1994 mustang gt 5.0L 302, my car will cut out while driving in all gears at all rpms and when i push the clutch in it will rev itself to over 2k rpms and wont drop till i tap the throttle then when it drops it will only drop to 1500 then will drop to normal when i am stopped idling for 15-20 seconds. Already Tried: I cleaned the idle air control motor Answer: This high Idle is a classic description of a vacuum leak. Most common place for the leak is the PCV valve hose located at the back of the engine under the upper intake manifold.