The fuel pump, located in the tank, supplies fuel through the filter (mounted on the engine compartment bulkhead) into the distributor under constant pressure. The fuel pressure at the distributor outlet is stabilized by a pressure regulator.
The fuel injection system consists of a control unit and the following sensors:
- throttle position sensor;
- coolant temperature sensor;
- flow meter;
- crankshaft rotation sensor;
- vehicle speed sensor;
- power steering pressure sensor;
- exhaust gas sensor.
The processor control unit compares the incoming information and generates signals that control the injectors, mixture composition and ignition timing.
Automatic stabilization of idle speed is provided by an air bypass valve controlled by the processor unit.
The throttle body has an automatic idle speed increase system on a cold engine, which is controlled by a thermostatic valve. As the engine warms up, the valve's working fluid expands, moving the valve plunger, which in turn acts on the throttle shaft cam, thereby closing the valve.
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The injection system also includes an electromagnetic valve for correcting idle speed when the engine load increases (for example, when turning on the power steering or air conditioning).
Attention! On some vehicles this valve is installed without connection (is inactive). In vehicles with a neutralizer, the processor unit also controls the emission control systems.
The control unit has a "failure protection" function, which, in the event of failure of one of the sensors, ensures the transfer of control to the backup simulating circuit, which allows the vehicle to continue driving, although with degraded operating parameters. In this case, a control lamp lights up on the instrument panel, and the malfunction is coded and entered into the control unit's memory.
If the warning light comes on, take the vehicle to the dealer's service center.
Attention! The control unit has a self-diagnostic function that enables independent reading of fault codes.