What's the difference between EFI and direct injection?

The biggest difference between EFI and direct injection is the control mode of injection. Direct injection is only mechanical injection, and EFI should be based on air flow, water temperature, throttle opening, knock engine load and other signals.

EFI is a kind of engine, which is quite different from carburetor engine. When the EFI engine is started, it is generally unnecessary to step on the accelerator, because the EFI engine has the functions of cold start and enrichment, automatic cold start and fast idle speed, and both the cold engine and the hot engine can ensure the smooth start of the engine. The EFI engine has high pressure and good fuel atomization quality, which is beneficial to the cold start and transition of vehicles; The fuel injection speed is fast and the penetration distance is long, which is beneficial to dynamic response.

In-cylinder direct injection (GDI) is a technology that directly injects fuel into the cylinder to mix with intake air. Its advantages are low fuel consumption, high power increase and high compression ratio of 12. Compared with the common engine with the same displacement, the power and torque are increased by 10%. At present, the disadvantage is that the components are complex and the price is usually expensive. The injection pressure is further improved, which makes the fuel atomization more detailed, truly realizes the accurate proportional control of fuel injection and intake air mixing, and eliminates the disadvantages of out-of-cylinder injection.