Just bought a car from a BMW dealer and the guy told me it was sitting for almost 6 months before I came to purchase it. When I left the dealership the oil was above the min mark showing green. Drove the car for 250 miles and the oil was at the min marker. When I started the engine this morning the oil level was yellow. I have added 1L of oil right away and it was still yellow then I added another one. Right now it is almost at max and I drove it for about 20 miles without any loss in level.
Can this be from the car being parked for this much or I should expect a low level tomorrow when I start it again?
Engine is a 3000cc diesel/2013 X6 M50d