Is there a way of telling if the PCV is shot?

I took mine off today, when giving it a slight shack, the component inside is rattling, also when blowing through the bottom (lovely taste of oil) there is no resistance, air come straight through.

 

Golden rule is, if it rattles, its ok. If it doesn't rattle is buggered.

 

Personally, if it's older than about 4 years, i'd change it.

 

Thanks guys, I'm going to change it as part of the service,
any idea on the UK part number? Struggling to get the right part.