The breather pipe from the pcv goes to the nsr of the cylinder head, where it connects into a T piece, these T pieces are always going bad and collapsing, it's on my dads car but I'll see if I can get a picture, I have ditched the pulse air and egr so a lot more room around there than normal.
Another thing to check is the EGPDS, a silver electronic box on the bulkhead area with TWO pipes leading from it into the EGR pipes, if the cat blocks up this will cause the top pipe to get blown off.
EGPDS is exhaust gas pressure differential sensor btw.
Can you send me some pics, I have pm'd you my email address.

tabetha