BMW series E90 idling a few days ago. Today, I cleaned the throttle and changed the spark plug, but I stopped idling just now. I saw it.

It's not the throttle, maybe it's more carbon deposit. Carbon deposition does shake the oil because it changes the compression ratio more, but not necessarily much. What is certain is that the combustion is not good, which is a fact. The burning is not because the oil circuit is not clean. The gas station should clean the oil tank and the car should take care of the added oil. Therefore, it is common that the combustion is not good and the oil circuit is dirty, but everyone does not realize this phenomenon. Cleaning the oil circuit regularly does not mean cleaning the carbon deposit, but the carbon deposit must be caused by the unclean oil circuit. You can add two general oil cleaners to the car, which will be clean, burn well and solve the jitter.