WARNING: This page is about a different car, the 2019 Audi A4 allroad, 2018 Audi A4 allroad, 2017 Audi A4 allroad, and 2017 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.
Special tools and workshop equipment required
Diesel Engine Tool Set: T10395B
with a suitable socket wrench