05-10-2013, 01:28 PM
pretty sure this is your piston ring seal on the exhaust side. they are pennies off ebay, but fitting them can be fiddly - cheaper to buy another td04 and fit it into your housing/setup if your not confident changing it.
![[Image: 22f2b6b2-758b-4c1c-96fb-6fa9c6059b13_zpsf306b56b.jpg]](http://i585.photobucket.com/albums/ss299/Ha11elujaz0rs/22f2b6b2-758b-4c1c-96fb-6fa9c6059b13_zpsf306b56b.jpg)