how did you check the diaphragm inside the pcv housing?? You have to break it open to look at it?
Do you get any sort of hissing sound when you shut the engine down from under the top engine cover?
I managed to get the pcv off ok no damage and it looked perfect.
It's funny you mention the hissing noise I don't think it sounds right.
It's not when you shut it down though.
I think ill be getting a forge catch tank anyway.
I'll try G247 which should come tomorrow.