HEllo ! My car is drinking about 1 lt of oil every 300 miles .No engine leaks ,driving just fine but when i leave it on idle for abt 5 min when accelerate there is some blue smoke coming out of the exhaust .I replaced the Pcv valve ( oil separator) but no results.Is a N42 engine on a 318ci,2003,M sport .the oil I;m using is 5w30 Castrol fully synthetic .Any suggestions ? thx