is it chuffing out blue smoke?! and is there alot of play in the turbo? i ask as its normal to find some oil in the boost pipes etc, obviously if the intercoolers half full with the stuff theres an issue but its nothing to panic about straight away if theres a film of it in the boost pipes.

my advice is drench the engine and any oily areas in halfords spray on engine degreaser, jet wash all the shit off then let it dry. once its clean and dry, run the engine and see if you can see where its coming from.