Fuel injection system parts (Audi A4 B6)

Electric fuel pump delivers fuel through distribution pipe (fuel distributor) to the valve injectors. Pressure regulator maintains constant pressure in the system and sends unused gasoline back to the fuel tank. The next important element is throttle control device. This device contains a throttle valve, which is connected to the accelerator pedal via a sensor and a control device. The more the accelerator pedal is pressed, the more the valve opens. At full throttle, the throttle valve opens completely. The above-mentioned throttle position sensor is also mounted here, as well as idle speed control valve. Under heavy load conditions in idle mode, such as when the air conditioner is running or when the power steering is turned all the way, this valve allows additional air to enter. The control unit uses air flow meter receives information about increased air consumption and issues a corresponding command to slightly increase the amount of injected air. Thanks to this, idle speed is stabilized. Electronic accelerator pedal slightly modifies the process described here. Information on this can be found in the corresponding technical dictionary entry in the previous chapter, which is devoted to engine management systems.



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