The fuel pump, as an essential component of the fuel injection system in an electronically controlled vehicle, is usually located inside the vehicle's fuel tank. Whenever the vehicle starts and begins to move, the fuel pump begins to operate. Its core function is to draw fuel from the fuel tank, pressurize it, and then deliver it to the fuel supply pipe. Additionally, the fuel pump works in conjunction with the fuel pressure regulator to establish and maintain an appropriate fuel pressure, while also providing the necessary signals to the fuel gauge.
The working principle of the fuel pump
In the early engine fuel systems, mechanical fuel pumps were dominant. However, nowadays, electric fuel pumps have gradually taken their place.
The working principle of the electric fuel pump is similar to that of the electric water pump. It drives the fuel pump device through an electric motor and continuously supplies fuel to the fuel system. The fuel system needs to maintain a certain pressure to ensure that the fuel sprayed by the fuel injector can be well atomized and easily combusted. After the engine is turned off, the pressure in the fuel system will gradually decrease, especially in high-temperature environments, and gas blockage may occur in the pipelines. To prevent the engine from being difficult to restart, a one-way valve is set in the fuel pump. When the fuel pump stops working, the one-way valve will automatically close to maintain the residual pressure in the fuel pipeline.
In addition, after the vehicle is parked for a long time, sometimes a "buzzing" sound can be heard coming from the rear when the ignition switch is turned on. This is not a fault but the electric fuel pump operating in advance to establish oil pressure for the fuel system. To prevent the pressure on the side of the fuel pump outlet from being too high, a safety valve has been specially designed. Once the fuel pressure delivered by the fuel pump exceeds the set value, the safety valve will open, allowing the excessive pressure of the fuel to flow back to the fuel tank.
The working principle of the fuel pump sensor is to use a sliding resistance plate to sense the oil level and transmit the resistance signal to the instrument. The instrument calculates the corresponding oil level based on the relationship between the liquid level height, the volume of the fuel tank, and the resistance value of the sensor, and displays it to the driver.
The possible causes of damage to the fuel pump
Including: Insufficient fuel in the tank, which prevents the fuel pump motor from being adequately cooled and lubricated, resulting in overheating or malfunction; Poor quality gasoline, containing impurities or foreign substances, accelerating bearing wear; Long-term failure to replace the gasoline filter, causing blockage and leaving the fuel pump inside in a high-load state; Malfunction of the fuel pump motor, with insufficient speed or complete failure; As well as open circuits or short circuits in the fuel pump wiring.
In addition, there are some basic tips regarding the use of fuel pumps that you should pay attention to: You should refuel at a reputable gas station to avoid damage to the fuel pump caused by inferior gasoline; when the fuel gauge alerts you, you should immediately refuel and avoid parking on a slope for a long time to ensure that the fuel pump can dissipate heat properly; when the vehicle is not used for a long time, it is best to park it on a level surface to prevent the fuel pump's oil storage box from being unable to store oil normally; at the same time, keep the fuel filler opening clean and clean up dust in time to prevent dust from entering the fuel tank, which could cause clogging of the filter, wear of the pump core or jamming.