Why do domestic cars consume so much fuel?

Now every consumer is full of praise for domestic cars, saying that the progress is extraordinary. Since the rise of domestic cars, the prices of cars produced by joint ventures have become lower and lower.

However, while praising domestic cars, we also have to admit the fact that domestic cars generally "waste engine oil". Domestic cars have developed for ten years. Why can't they catch up with the joint venture car in terms of fuel consumption?

Before solving this problem, let's talk about the four main factors of automobile fuel economy: engine, gearbox, body weight and drag coefficient. Among them, the engine and gearbox are the soft underbelly of domestic cars. At present, the engines on the market include multi-point injection, in-cylinder direct injection and mixed injection. Most domestic cars use multi-point injection, which is an extension of single-point EFI. It injects fuel directly into the intake manifold of each cylinder. Compared with in-cylinder direct injection, multi-point injection has an earlier development time and more mature technology, but its fuel economy is poor. In-cylinder direct injection was born under the trend of adapting to society. Its advantages are energy saving and emission reduction. It really saves fuel. Its disadvantage is that it is easy to cause more carbon deposition. Knowing this, you should know why domestic cars are more expensive than joint venture cars. In-cylinder direct injection represents the current development trend. At present, domestic cars have no research and development capabilities. Many domestic cars are still engines produced by joint venture brands. What they provide for domestic cars is outdated multi-point injection. Although the performance is stable, it also costs oil. Most joint venture brands use in-cylinder direct injection. At present, only 10% domestic cars use direct injection in the cylinder, which is a large proportion. The reason is that the use of in-cylinder direct injection needs to pay a higher price. Domestic cars will definitely choose multi-point injection before in-cylinder direct injection and multi-point injection. Before in-cylinder direct injection was widely used in domestic cars, joint venture brands began to use mixed injection again. Mixed injection has further expanded the distance between joint venture brands and domestic cars, which is actually as wide as the Pacific Ocean.

Then there is the gearbox, and the mismatch between gearbox and engine will also increase fuel consumption. At present, some domestic cars have made great achievements in engines, but they have always relied on the outsourcing of gearboxes. The gearbox is like a bone on the top of a car. Without it, cars cannot run smoothly. However, the purchased gearbox cannot match the engine 100%, and the running-in of two strangers will increase fuel consumption. This is also a major reason for the high fuel consumption of domestic cars.