I have a 2000 A6 Quattro, 2.8L, with 141K miles. Yesterday, as I was driving home the Oil Light came on. I was two blocks from home so I drove back and pulled in the driveway. As I pulled in I could hear a loud ticking sound, like a lifter or valve. I checked the oil level and I was about 1 quart low, so I topped it off. I started the car and the ticking was still there, not quite as loud, and the oil light is still on. Does anyone have any suggestions as to what may be causing this? And even more so, is the motor blown?? There is no smoke from the exhaust. Thank you for any direction you can provide.