Working Principle of Electronic Fuel Injection System

Working Principle of Electronic Fuel Injection System

The electronic control unit (ECU) receives real-time operating condition information from sensors such as crankshaft speed sensor, coolant temperature sensor, air flow sensor, accelerator pedal position sensor, and needle valve stroke sensor. Based on pre-set and stored control programs and parameters or graphs within the ECU, it performs data processing and logical judgment to determine suitable control parameters for the diesel engine's current operating conditions. These parameters are then converted into electrical signals and sent to the corresponding actuators. The actuators, according to the ECU's instructions, flexibly change the opening and closing timing or the on/off state of the injector solenoid valves, adapting the combustion process in the cylinders to the changing needs of the diesel engine under various operating conditions. This maximizes diesel engine output power while minimizing fuel consumption and emissions.

If sensors detect parameters or conditions exceeding the set range, the ECU stores fault information and illuminates indicator lights on the instrument panel (alarming the operator). If necessary, it automatically cuts off the fuel supply or closes the intake valve via the solenoid valve, reducing the diesel engine's output power (or even stopping the engine) to protect the engine from serious damage. This is the emergency protection mode of the electronic control system.