Am I right in thinking that the PCV valve on my 2005 4.6l should only be a one-way valve?

I was under the hood yesterday and decided to see if it is a one-way... but I could move air through both ways with my mouth.

If it is only supposed to be a one-way, do I need a specific model replacement or can I just goto autozone, ect. and get a universal one?

 

go to autozone and look it up in the book. should have them in stock.

 

Motorcraft brand though?

I've heard about other companies causing a "buzzing" sound when installed on our trucks.

 

Always MC


Dennis