Q: What type of oil does an Audi A4 quatro 2009 use?

You can use 5W-40 synthetic oil that meets Volkswagen standards 502.00 and 505.00. Alternatively, you can use 5W-30, 0W-40, or 0W-30. If the light you are referring to is a low engine oil level warning light and the oil level is actually OK, then the warning light circuit should be diagnosed and repaired. If the light is the oil change maintenance reminder light, be sure to request an oil/filter change. Finally, if the light is a low oil pressure warning light, that is a serious fault and should be investigated immediately. Obviously, if there is no oil pressure, be sure not to run the engine at all. If you have further questions or concerns, please do not hesitate to re-contact YourMechanic as we are always here to help you.