I am sure I drained total 3.3-3.5L old oil from drain plug and check plug , filled in 2.8-3.0L, idle engine for 20min, then pulled check plug (5mm Allen plug), drained another 1.2-1.5L. So I only have about 1,5L fresh oil in the pan compare to 3,5L before drained. I heard that there is saying...