Hey Dan
My last 16v developed exactly the same problem at 120k. Horrible clattery noise which is quite unnerving.
The garage is use said they had never come across one which had actually snapped so I could live with it if I wanted. Of course I didn't want to so I had it repaired. I think they changed the chain, sprokets and the tensioner. They advised me to change the hydraulic tappets (x16) at the same time to save opening it up again at a later date, while the cams were off it seemed logical to have the cambelt done at the same time.
The garage bill was quite a bit in the end about ?500 but afterwards it did sound pretty sweet and pulled equally aswell. Mind sound expensive but unless all the other jobs have been done recently it does make sense to do it all while it's apart.
Toby
