How does the EFI engine work?
The principle of single-point injection and multi-point injection: Single-point injection system (SPI), also known as central fuel injection (CFI), is also composed of three parts like the multi-point injection system: oil supply part, gas supply part and control section. The oil supply part is composed of a fuel tank, an electric fuel pump, a fuel filter, a pressure regulator and a central injector. The electric fuel pump is generally installed in a fuel tank, and the system pumps the oil out of the fuel filter at a low pressure of 0.1 MPa. The impurities are filtered and sent to a central injector for ejection. The air supply part is composed of an air cleaner, a throttle valve, an intake manifold, a cylinder, and the like. When the air is sucked into the throttle valve, it starts to mix with the atomized fuel to form a mixed gas, and is distributed to each cylinder through the intake manifold. The control part is composed of an electronic control unit (ECU) and various types of sensors. The main sensors include a throttle position sensor, an oxygen sensor, a crank position sensor, etc., which feed back signals to the ECU, and the ECU issues a work command to an actuator such as a center injector.