Air is drawn in by the engine through the air filter and air intake pipe and is measured by the air mass meter. In the case of the air flow meter there is a damper, which is deflected by the air passing through it at a certain angle. The angular position of the damper serves as a measure of the amount of air passing through. Information about the amount of passing air is transmitted to the control unit from the potentiometer.
The control unit regulates the injection time and thus the amount of injected fuel in accordance with the measured air mass. With a longer opening of the nozzle, more fuel has time to be injected. Additional sensing elements and sensors ensure the supply of the right amount of fuel even in extreme driving situations.
1. Fuel tank
2. Fuel pump
3. Fuel filter
4. Fuel pressure regulator
5. Electronic control unit
6. Ignition coil
7. High voltage ignition distributor
8. Spark plug
9. Nozzle
10. Throttle
11. Throttle switch
12. Air flow meter
13. Potentiometer and air temperature sensor
14. Lambda probe
15. Temperature sensor
16. Idle speed regulator
17. Inductive pulse sensor
18. Battery
19. Ignition switch
20. Air conditioner switch
The throttle switch is located directly on the throttle shaft. It supplies the control unit with throttle position signals in idle and full load positions. As a result of this, control is primarily carried out in the forced stroke mode: as long as the throttle valve contact is closed and at the same time the speed exceeds a certain value, the control unit blocks the fuel supply to the engine.
The fuel pump relay is located in the relay box at the left rear of the engine compartment. It supplies power to the fuel pump. When you stop receiving pulses from the speed sensor with the ignition on (with a stalled engine) the control circuit interrupts the power supply.
The current position of the crankshaft of the engine and the speed are determined by 2 inductive sensors: The speed and reference mark sensor is located in the mount on the crankshaft pulley, the cylinder identification sensor is an inductive loop on the ignition wire of cylinder 4.
Lambda probe (oxygen sensor) measures the oxygen content in the exhaust gas stream on vehicles equipped with a variable catalytic converter and transmits the corresponding electrical signal to the control unit. Based on this information, the control unit changes the composition of the intake air-fuel mixture in such a way as to ensure optimal afterburning of the exhaust gases in the catalyst.
The idle air control regulates the amount of air in idle speed in the throttle area. As a result, a stable speed is achieved, regardless of whether additional consumers such as power steering or air conditioning compressor are connected. The idle speed controller is controlled by the electronic control unit of the fuel injection system.
The coolant temperature sensor measures the engine temperature, which has a big impact on fuel consumption.
The activated charcoal tank collects fuel vapors from the fuel tank. When the engine is running, these vapors are supplied in portions through the fuel tank ventilation valve to the engine, thereby reducing emissions of harmful substances and saving fuel.