PCV how to check?

[jdavis]

Hope you guys can help, my 850 t5 has developed an annoying drip of oil and is going through a noticeable amount. No drop in performance. Bit of investigation pointed to upper engine so I purchased new rear camshaft seals as they are a known spot. Gone to change these this morning and it's coming from above there, from the rocker cover area. Took the plug cover off and found it with a fair amount of oil in there. My only thought would be the oil filler cap. Clean it up, cleaned the filler cap seal etc then thought about what could cause that and I'm stuck at either dodgy filler cap seal or excessive pressure in engine, ie, a blocked pcv system. The guy I bought the car off said it had had the pcv done but there's no documentation. I've heard one way of checking I'd to pull the dipstick and look for vapour.
This is the result of that
https://youtu.be/As06v2lQBYw

Are the filler cap seals known to leak?

[Doingitsideways]

Dipstick check looks good to me (although I am viewing on a phone)

Another way is to stick a surgical glove over the oil filler neck and let it idle, if the glove inflates, there may be issues there.
(This is a generic test, can't think of any reason why it wouldn't apply here)

Oil filler cap seals to leak though, easiest way to tell is to look under the spark plug cover, as it pools in there first.

[kmb]

He has mentioned oil under the spark plug cover, so it sounds like you've hit the nail on the head...

[jdavis]

Thanks guys, £14 for a new genuine oil filler cap and seal. Ordering in the morning.

[PNuT]

To check if your pcv is blocked pull the larger pipe of the air induction pipe just before it heads in the turbo.... on this diagram http://www.matthewsvolvosite.com/images/oiltrapv701jx.jpg its number 9.... with the enging running you should feel a little pressure from it.... if you feel nothing it is most likely past its best