good day, i have a 6 month old nav d40 diesel 4x2 with 12000 km mileage, I've checked my dipstick while the engine is running and white smoke appeared continuously and the engine is in normal temp operation. when i the engine is cold and running, there isn't any sign of the white smoke. what could be the cause? the pcv is not clogged, it performs like normal, doesn't eat oil and the coolant is always in normal level. does it have to do with the oil used? or do i have a more major problem to face like blown head gasket or overhaul this early stage? TIA