1.0. Sensors and actuators of the injection system:
1 - 4-pin plug of the main lambda probe 1 (Green colour)
2 - 4-pin plug of the main lambda probe 2 (Brown)
3 - 4-pin connector for additional lambda probe 1 (black color)
4 - 3-pin knock sensor 1 plug
5 - coolant temperature sensor
6 - boost air pressure reducing valve
7 - adsorber purge solenoid valve
8 - sensor 1 and sensor 2 exhaust gas temperature
9 - not used
10 - electric motor of the pump of the afterburning system
11 - valve for supplying fresh air to the exhaust valves
12 - turbocharger bypass valve
13- fuel pressure regulator
14 - camshaft position sensor (Hall Sensor)
15 - afterburner pump relay
16 - engine control unit
17 - 3-pin plug of the crankshaft position sensor / engine speed
18 - 3-pin knock sensor 2 plug
19 - 4-pin connector for additional lambda probe 2 (black color)
20 - camshaft position regulator valve
21 - throttle valve
22 - boost air pressure sensor
23 - camshaft position sensor (Hall Sensor)
24 - ignition coil with output stage (cylinder head 1)
25 - ignition coil with output stage (cylinder head 2)
Fuel is drawn from the fuel tank by an electrically driven fuel pump and fed through a bottom mounted fuel filter to the fuel injectors. The pressure reducing valve maintains a constant pressure in the fuel system.
Fuel is supplied through electronically controlled valve injectors, i.e. intermittently injected into the corresponding intake manifold pipe just before the engine intake valves. The engine control unit regulates the duration of injection and thus the amount of fuel injected.
Air is taken in by the engine through the air filter and through the throttle valve and intake manifold to the intake valves.
The amount of incoming air, taken into account by the air mass meter, which uses a film as an filament element, determines the amount of fuel that the injectors must inject.
The body of the air mass meter contains a thin sensitive film that functions as a filament. Passing near this film, the air taken by the engine cools it. The control unit regulates the heating of the film in such a way as to keep it constant, reacting to the volume (mass) incoming air by increasing the filament current. By changing the filament current, the control unit determines the load on the engine and accordingly regulates the volume of injected fuel.
The information received by the control unit from other sensors, as well as the commands given by the control unit to actuators or control mechanisms, ensure optimal engine operation at any current load. If one or more of the main sensors fails, the control unit executes an emergency program to prevent damage to the engine and ensure continued movement. Sensor failure should not be immediately suspected when engine performance deteriorates. Appropriate conclusions can only be drawn when performing a CO check or after receiving information about malfunctions in the injection system.
The throttle valve is part of the fuel injection control mechanism.
The main task of the injection control mechanism is to maintain a stable idle speed of the engine under all operating conditions and engine loads.
The idle speed sensor transmits information to the control unit about the throttle opening angle at idle. The control unit opens or closes the throttle by means of an executive motor, thus maintaining the nominal value of the idle speed.
The coolant temperature sensor and the intake air temperature sensor register and report current temperature information to the unit by decreasing their resistance as the temperature rises.
The fuel tank is vented by means of a container with activated carbon and a solenoid valve. Activated carbon absorbs fuel vapors that form in the tank. When the engine is running, the fuel absorbed by the coal is released and it enters the engine for combustion.
Lambda probe (oxygen sensor) determines the oxygen content in the exhaust gas and transmits the relevant information to the control unit by changing its resistance.
The knock sensor is used to determine and maintain the optimum ignition timing.
The duration of the opening and closing of the intake valves is regulated depending on the engine speed. To do this, the intake camshaft has a regulator that changes the moment of rotation of the shaft relative to the exhaust camshaft, providing a later closing of the intake. This achieves a smoother running of the engine at idle and an increase in its power at high speeds. To increase engine torque at low and medium speeds, the camshaft positioner is activated and the intake valves close earlier, providing improved filling of the cylinders.
All parts of the ignition and fuel injection systems are designed for a long service life and practically do not require repair. As part of the maintenance, it is only necessary to change the removable filter element of the air filter, as well as the spark plugs.
Basic adjustment and repair work can only be carried out using expensive instrumentation. For this reason, repairs and adjustments should be entrusted to specialized workshops with the necessary instruments and devices.
Adjustment of idle speed and CO content is not required as part of maintenance.
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