No way can anyone answer this here. Changing a timing belt is too complicated to explain here. Get yourself a repair manual or pay an expert to do this. It must be done correctly or engine damage can...
Change the oil in Audi A4: I recently changed the oil in my g/f's Audi A4. The manual calls for a 5w-40 oil which you probably wont be able to find. A 5w-30 or 10w-40 is acceptable if your climate...
Facing the car the air box is to the left. Undo four clips, remove element, clean out the air box, install new element (read the arrows for the direction of the air flow), reattach clips.