I have a 2002 Audi A4 1.8 and an oil can writing "OIL" below it appears on the middle of the LCD screen followed by three beeps. I do not have an owners manual but i think it means that oil pressure is low. When i push the "check" button it says "SWITCH OFF ENGINE, CHECK OIL LEVEL". Oil level is normal. Just changed oil a few days ago with Mobil1 5W30. The engine was flushed about 4 months ago and no signs of sludge appeared. The car runs great with no weird noises or anything unusual. The oil sensor was leaking so i put in a new oil sensor but that didn't solve the problem. The warning light comes on after i drive about 5 miles. What could it be?

 

I have the same problem. its annoying i need to figure this out to fix it. I believe its just a sensor gone bad

 

Luckily mine was just a bad sensor

 

have you suddenly switched from regular to synthetic oil? this happened to mine when i did that at 110k. usually it happens a lot earlier than 110k but from what i understand....and was shown once it was apart. there is a small neck with a filter in it that keeps stuff from making it to the engine and that usually has to be dropped and cleaned or replaced (somewhere near 50k is normal for those). mine didn't happen until right after the switch in oils and the way the synthetic reacted to the deposits left from regular oil....loosening them and letting them into the filter and slowing the oil pressure. usually it can be cleaned. i replaced mine and we scrubbed the pan so you could eat off of it...and that was the last time it went on.

p.s. it went on within 5o miles of the oil switch, it's pretty immediate (th reaction/loosening) from what i am told.