Took it down to Tenagah today to get it diagnosed and yeah, it was an exhaust manifold leak. Leaking from all the slip joints ..
They reckon it might have been caused by the ceramic coating, saying that after u coat them and join all the pieces together, the fitment is all good when the coat is fresh and new. But when the coat wears away, it beings to leak as the fitment isnt as snug as with the coating.
Just gonna go back to the stock manifold with an aftermarket up pipe(wrapped) and maybe change the cross over pipe aswell.
Anyone willing to take these off my hands when they are off(should be in the next 2 weeks)? Im sure theres a way around the leaking joints. P.M me if your interested, ill let them go real cheap.
Cheers
-Nick
EDIT:
http://www.perth-wrx.com/vb/general-subaru-discussion/14512-xforce-headers-pics.html
If your interested in the headers, they are number 2 in the above thread, first post. They also have black heat coat on them.