Originally Posted by AsleepAltima

sounds like the idle air control valve is dead. its located behind the #1 cylinder below the intake manifold. look down in there and locate the large phillips headed screw. give it a turn or 2 counter clock-wise. the rpms should come up. if the car wont start for you to do this, get in and floor the gas pedal and try to start the car. once you get it started, try messing with the screw. sometimes you can remove the iacv and clean the carbon out of it and it will work again for awhile.
im kind of curious about the people that replaced the pcv valve. this is like a 4 hour job and would have cost you about 250 bucks to have done... did they really do it?