Guidelines For Clean Working Conditions

WARNING: This page is about a different car, the 2021 Audi S4 and 2021 Audi A4 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

Thoroughly clean connecting points and their surrounding areas before loosening.
Place removed parts on a clean surface and cover them so that they do not get dirty. Use foil and paper. Only use lint-free cloths.
Only install clean parts: Remove the replacement parts from their packaging just before installing them.
Only use greases and sealants that are designated with part numbers.
Carefully cover or seal opened components if the repair is not performed immediately.