Oil in a Volkswagen Passat 2001 1.8t

well your first mistake was using the wrong oil for the wrong engine. Who ever told you to put 10w30 into your car was a complete idiot. The cars manual and the oil cap should both state 5w40 FULL Synthetic engine oil *Only* If your piston rings and valves are not already fried they will be in the near future. Get the oil out of your car and use some engine oil clear Lucas if you can and clean that oil out best as you can. Walmart or canadain tire should have the oil your looking for. It will be castrols 5w40 full syntheic. The car requires 6 L of oil i think it may be 5 L for the 1.8L engines.

This is a picture of the jug

dude, that answer is a little extreme for just that little difference. you dont have to clean it out or replace it, the manual might give a specific oil type but its recommended not mandatory. just be sure to get the recommended type next time you change the oil and you'll be fine. flushing an engine for that minuscule difference is the type of suggestion you get from the forum guru that knows everything about everything but in actuality looks it up because he really dint know