[Xtra_X]

What your refering to is the PCV Valve. It' shouldn't be replaced with a filter. They may be refering to a Valve cover breather. which is on the driver side rear of the valve cover. It connects to a long tube which runs down to the air box. Regardless neither of these should cause a whine. At the most just a rought Idle. Whines usually come from the accesories like the water pump/ac/ alternator as well as anything the serpintine belt turns including the idler.
hope that helps