The PCV valve is a Positive Crankcase Ventilation valve...it takes the blow by that gathers in teh crankcase and puts it back into the intake to be reburned. the downfall is that some oil gathers there too. it usually just burns too...no harm is done to the engine...just thought i'd fill you in on the purpose of the PCV valve
72Mavguy - You gave a good description of the purpose of a PCV valve. I'm confident you also know that what is in the picture is not a PCV valve. That is a temperature controlled vacuum switch. I believe this may be an A/C equipped car and the vacuum switch is part of the A/C and heater control system.
