Diesel fire pump metering solenoid valve failure, what can be done to increase pump suction
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What to do if the diesel fire pump metering solenoid valve is faulty? Fuel metering solenoid fails, does the engine catch fire? Can you ignite and affect engine performance? When the fuel metering solenoid valve fails, it will hit the engine. Whether it disobeys it should be based on the specific model and consideration. Even if the same electronic control system is used, some models can play a fire role, and some models cannot. It depends on the system. Control strategy. The following are specific examples.
(1) Great Wall gw2.8tc supercharged common rail diesel engine. When the fuel metering solenoid fails, the engine cannot start and run. When the fuel metering proportional solenoid fails, such as binding, cannot be opened, resulting in high-pressure fuel rails. This failure phenomenon occurs because the fuel oil contains more impurities, and the proportion of the fuel metering solenoid can be cleaned. The fuel metering proportional solenoid valve consists of The ECU connection line is disconnected, which causes the ECU to fail to control the fuel metering proportional solenoid valve, which prevents the engine from catching fire or starting. Note: The fuel metering solenoid valve used in the vehicle is usually closed. (2) Weifang Yuchai Diesel Chaiguo III Bosch diesel common rail system is open. When the fuel metering solenoid fails, the engine can start and run normally (limping home-limping home). When the ECU determines that the fuel metering valve is malfunctioning (such as the fuel metering valve is damaged, the drive circuit is open and shorted), the ECU takes a series of measures: Light up the fault lamp; (1) Fault codes p0251, p0252, p0253, p0254, p025c, p025d; Fuel pressure and pressure limiting valve high-pressure drive: The diagnostic instrument shows that the rail pressure increases at 700-760bar and increases with speed. The speed of the diesel engine is limited, and the throttle valve is still working within the limited range. After the ignition switch is turned off, the fuel pressure release valve is closed normally; if the engine startup process has entered this strategy, it can still be started without any obvious feeling. (3) Ⅲ Yuchai Delphi diesel common rail system When the fuel metering solenoid valve fails, the engine cannot start and run. When the ECU determines that the fuel metering valve is malfunctioning (such as the fuel metering valve is damaged, the drive circuit is open and shorted), the ECU takes a series of measures: To shut down or fail to start; fault codes: p0251, p0253, p0255. In the case of a gw2.8tc diesel engine, the fuel metering proportional solenoid valve has two terminals, the # 1 terminal of which is connected to the 49 # terminal of the ECU, and the # 2 terminal is connected to the A19 # terminal of the ECU. gw2.8tc diesel fuel metering proportional solenoid valve and ECU circuit connection. (1) Outside inspection. The resistance between 1 # terminal and 49 # terminal, 2 # terminal and A19 # terminal are measured with multimeter resistance to determine if there is a short circuit or disconnection fault in the external circuit. (2) Sensor resistance measurement. Turn off the ignition switch, remove the fuel metering proportional solenoid valve plug, and measure the ## sensor side resistance between terminals 1 and 2 at 20 ° C. The resistance between the two terminals should be 3Ω. (3) Whether the work is abnormal. The fuel metering proportional solenoid valve is closed when closed, and the connection between the low-pressure oil circuit and the high-pressure oil circuit is cut off. Therefore, when the ignition switch is turned on, the fuel metering proportional solenoid valve should be able to hear continuous buzzing sounds, and the handle should be able to feel obvious vibration; (4) Data flow detection. Special a30ck diesel fault diagnosis instrument measuring God "can read" oil supply value of oil metering unit "," duty ratio of oil metering unit output "and" rail oil pressure controller control counter value "three parameters, such as data flow . The parameters of the Bosch common rail system fuel metering solenoid valve are as follows: Frequency of PWM signal: coil resistance: 2.6-3.15 ohms; maximum current: 1.8a. Special note: The fuel gauge proportional valve is normally open and normally closed. Pay special attention to maintenance. First: a suction bottom valve is installed at the suction pipe end of the suction pump. The suction bottom valve is actually a check valve. It guarantees that the water can only be drawn by the pool suction pipe and cannot be reversed. Therefore, if the suction pipe is filled with water, although the upper level of the pool water pump axis is elevated, the role of the suction bottom valve in the suction pipe Water will not flow into the pool, so that the suction pipe will always be filled with water to ensure that the pump can start automatically and quickly. The reliability of this water absorption method is affected by the water quality of the bottom valve, such as closed, leaking air, the water inlet pipe can sink slowly, the time is prolonged, the water suction pipe is empty, and the pump needs to be manually irrigated to start. Second: The self-priming pump reduces the curvature, height and horizontal distance of the intake pipe. Third: self-priming pump pump water tank. This method requires a water tank to be installed in the suction pipe of the pump. Before the first operation of the pump, the tank should be filled with water manually. After stopping the first operation, the height of the water inlet pipe is higher than the height of the pipe surface, although it is lower than the water tank. The height of the water tank, the water in the water tank will not flow back into the pool, so the water tank can store a certain amount of water. Because the height of the water tank is lower than the height of the outlet pipe of the tube, so that the suction pipe pump is filled with water, run the pump again, and the water tank The water is a negative pressure in the drainage pump and the tank. Under the effect of atmospheric pressure, the water in the pool is added to the water tank and passes through the pool in the absorption pool. Fourth: Self-priming pump Install the vacuum pump on the suction pipe of the pump. Before the pump is started, the vacuum pump is started, and the water pump is first filled with water, so that the water pump can automatically and quickly start. This suction method requires a perfect automatic control system to ensure normal work.