I just changed the oil on my M3. I put in 8.2 liters and started the car. After it warmed up idling, my indicator showed that I needed to add 1 quart. I put in 600 cc more for a total of 8.8 liters added. There are no leaks under the car. I took it for a short run around town and it still indicated low. Today I took it for a 40 mile drive and it's still indicating low. I know I put 8.8 liters in so I don't want to add any more. Please help,with any suggestions.