ok...

1. could be rings, do a compression test/ leak down test

2. could be a turbo issue, my turbo failed by chucking oil out of the inlet side..net result oil in th turbo tubes...into the trottle body which under boost forces oil back UP the mini tube to the 'flame trap'...

3. do you have flame trap fitted..if so you shouldnt, if its this thats blocking remove it

4. If your turbo is overheating you have a problem.

5. i would gues you have a failing turbo, remove ALL the large diamet er air pipes and clean THOUROUGHLY and drain and clean the IC, then do some miles and se what oil is about in them, anything more than a misting is a problem...also check your turbo free play, pretty much if you can feel any its toast!

6. When my turbo was going i found that the BIG pipe from the breather to the inlet was badly coaked and i had to tdo SERIOUS cleaning to get it to flow well i.e. platic cloated wire and solvent and a good rodding..

7. You have replaced the breather box havent you? if not DO IT NOW they can block and do all sorts, u can clean but not worth it...just replace (see faq!) easy job and worth it..

8. If you have that much presure I would suggest you sort as a matter of urgency, best case is you loose a cam seal, but you can loose the rear seal which is big PITA or $$$...