B9 RS4/RS5 Field Service Action - Breather Pipe

[Evil Derboy]

I've posted the details of this in the RS5 section but it affects B9(8W) RS4 owners as well:

https://www.audi-sport.net/xf/threads/b9-rs4-rs5-field-service-action-breather-pipe-10f8.378188/