If you think its your PCV valve grab a 3/8 extension and a pair of pliers. Hold the extension next to the valve put your ear on the other end (engine running of course) and squeeze the tubing shut with the pliers. It should make a clicking sound once and then when you release it click again. If it does its in good shape.
With a boosted engine you might be sucking a little oil up into the intake manifold which can really clog up the IAC valve screen. Bleh there are a ton of variables my suggestion since I dont know what car/engine/setup/etc is just to grab a shop manual and a multimeter. Go out and trouble shoot the system.