The Audi S4 features a special design of Audi factory wheels, called Avus wheels. The wheels have caps at their centers to help protect the lug nuts, which secure the wheel to the wheel hub, as well as the wheel hub assembly itself. It is a good idea to remove the center caps from the wheels to clean the area underneath. Even though the center caps help protect this area from the accumulation of water and dust, some dirt can still make its way inside. Fortunately, removing the center caps is a very easy process.
Park your S4 on a level surface, leaving the transmission in gear with the emergency brake engaged, to ensure that the car will not move.
Insert the tip of the flathead screwdriver in between the center cap and the wheel assembly. There will be a small notch on the center cap to facilitate the insertion of the screwdriver. You can locate this tab by following the circumference of the center cap
Pry the center cap away from the wheel and wheel hub, which helps secure the center cap to the wheel. Repeat steps one through three until you have removed the center caps from the remaining wheels.
Park your S4 on a level surface, leaving the car in gear and the emergency brake engaged, then pop open the trunk.
Open the tool kit that's located on the driver's side of the trunk and locate the wire ring that's stored within it.
Insert the end of the wire ring into the hole that's located on the black ring at the center of the wheel's center cap.
Pull the wire ring firmly once you have secured it to the center cap, to remove the cap. Repeat these steps on the remaining center caps that you wish to remove.
