Why do some people say that German cars burn engine oil? Is there a basis?

It is said that German cars burn engine oil. As we all know, the power of the car comes from the engine, and the power of the engine comes from the reciprocating motion of the piston in the cylinder. With the increase of engine working temperature, the piston and cylinder will conduct heat, cool and contract, which leads to the need to reserve a small gap between the piston and cylinder wall at the beginning of engine design, and the oil plays the role of lubricant. However, with the reciprocating motion of the piston, the engine oil remains on the cylinder wall and is consumed with the combustion of the engine, which is the reason why the automobile burns engine oil. However, the phenomenon of burning engine oil in some cars is very slight, so slight that you can't notice or ignore it, while some cars are more serious. According to the authoritative American magazine Consumer Report, the models released in the past few years were investigated, among which 30 models showed outstanding performance in the oil circuit. Among them, 23 models are German cars, including BMW, Porsche and Audi.

This is related to the transportation environment of German cars. Because there are many freeways with unlimited speed in Germany, German cars are often in a high-speed state, and they can run for two or three hours at a speed of 200 kilometers per hour, which puts extremely strict requirements on engine lubrication. In order to meet this need, a large gap will be reserved between the piston and cylinder walls of German cars. At the same time, the cylinder wall surface of German cars is often not a smooth metal surface, and the cylinder body often adopts a mesh structure, also known as an oil storage structure.

In this way, the cylinder wall absorbs more and more evenly, so that the piston ring is easy to form an oil film when moving, which plays a better role in lubrication protection; Of course, this also leads to more residual oil on the cylinder wall of German cars, so cars in other countries often do not need to consider this limited lubrication, so the gap between its piston and cylinder wall can be smaller, and the cylinder wall is a smooth metal surface, and there will be little residual oil on the cylinder wall; There are also some phenomena of burning oil, but they can be ignored.

German cars do burn oil, but not all German cars burn oil. For example, Mercedes-Benz engines rarely burn engine oil, while BMW and Volkswagen self-priming engines rarely burn engine oil. Only a few Volkswagen and BMW engines burn oil seriously. How many engines can represent German cars? However, due to the large sales volume of the public, the problem of burning engine oil has been amplified. Small brands can't sell a few cars a year, and the biggest problem is ignored.