The rather common problem of BMW 3 E90 is the increase in oil consumption after 30,000 km of mileage. Oil consumption can reach one litre per 1,000 km, but in general this figure depends on the driver's drive.
One of the reasons for the increased oil flow can be oil-removable oil rings, which are either quickly destroyed without working out their useful life or buried.
Also, the cause of the large oil consumption may be over 25,000 km. That is why BMW 3 E90 owners are recommended to change the engine oil once for every 7,000 to 10,000 km.