I swap PCVs about every other oil change. I have two, a clean one goes in and I clean the other and set it aside.
Uh, gotcha. I have that sound but I only hear it after I shut the engine off. I'm not exactly sure what it is but my guess is the charcoal canister. Mine is more of a gurgle than motor, hard to describe. It continues for a minute or two and sounds like it's coming from behind the kick panel almost.
I'd still be checking the EGR, fuel pressure regulator and IAC. All of those are motors, sorta, vacuum or in the case of the IAC wax moves a diaphragm anyway. I bypassed the VSV for the fuel pressure regulator on mine since it was causing a funky idle, although running it from manifold vacuum also can make it oscillate. But at least it's consistent.
'91 Toyota Pickup
'09 Kawasaki KLR650
'12 Gunnar Rockhound 29
"They say the test of literary power is whether a man can write an inscription. I say, 'Can he name a kitten?'" -- Samuel Butler