Nowadays, excavators mostly use electronic injection engines. Various alarm codes may be encountered during use, and these alarms are mostly caused by sensor or solenoid valve failures. This article will introduce the functions of engine EGR valve, injector connector and common rail pressure sensor. When the excavator has an alarm code, after knowing the meaning of the code, it can be checked and replaced according to the position of the sensor and solenoid valve.
1. EGR valve
EGR valve is a variable opening solenoid proportional valve controlled by ECU. ECU makes judgment according to engine speed, water temperature, common rail pressure and other information. Adjust the opening of EGR valve to make a proper amount of exhaust gas enter the combustion chamber again. It can not only not affect the engine power, but also reduce the content of nitrogen oxides in emissions.
2. Injector connector
It is used to keep the control signal connection between the solenoid valve and ECU in the injector. The ECU receives the accelerator sensor, speed, water temperature, common rail pressure and other information. Commands the injector solenoid. In order to control the start time and stop time of injection, the fuel supply advance angle and injection can be adjusted. So as to control the engine speed and torque.
3. Common rail pressure sensor
It is used to feed back the high-pressure diesel pressure signal in the common rail chamber to the ECU. Due to the high-pressure injection adopted by the common rail diesel control system, the injection pressure is more than 10 times higher than that of ordinary direct injection engines. Therefore, ECU will monitor the diesel pressure in the common rail cavity in real time and judge according to the feedback pressure signal and other feedback signals. Send command signals to injector solenoid valve, EGR solenoid valve, SCV valve and other control units.
