PCV valve

[reborn55]

Went to put new PCV valve in wife's coupe--77 350 and noticed that the new one vibrates--rattles--not fully sealing with motor running.  Old PCV valve sealed tightly when running--no pulsating/rattling.  Brand new NAPA valve correct fro the motor.  Problems?--or not to worry.  Has 19 inches of vacuum at idle.

[unklian]

How would it work, if it was sealed at idle ?

[reborn55]

Not really sealed.  Just not bouncing around at the top of the valve. Still having vacuum ability