- 1. Electronic fuel injection. The control unit receives signals from various sensors that transmit data on operating conditions, including intake manifold pressure, intake air temperature, coolant temperature, engine speed and engine acceleration or braking. This data is evaluated by a microprocessor to determine the exact injection timing to create the optimal air-fuel mixture.
- 2. Electronic control of ignition timing. The electronic control unit is programmed with data for optimal ignition timing. With the help of the various above-mentioned sensors, a spark is produced by the spark plugs at the right moment.
- 3. Diagnostic function. The control unit registers every failure or malfunction in the system and lights a warning lamp on the dashboard. At the same time, the microprocessor stores the failure. Thanks to this, the failure is detected immediately at the service station.
- 4. Failure monitoring. In the event of a microprocessor failure, individual functions are performed by a backup circuit, allowing the vehicle to be driven to the nearest service station. This will cause the warning light on the instrument panel to come on.
Figure 138 shows a diagram of the injection system on a 2.0 l engine, indicating the position and connections of individual parts. The figure shows the system working with the catalyst as it is installed on most cars. Similar parts are used on the 1.6 liter engine running with a catalyst.
Pic. 138. Diagram of electrical and fuel connections of the fuel injection device of the 2.0 l engine: 1. Ignition switch; 2. Fuel pump; 3. Fuel tank; 4. Fuel filter; 5. Battery; 6. Ignition distributor; 7. Ignition coil; 8 Warning lamp "Check"; 9. Air conditioning compressor; 10. Control socket (T-E1); 11. Supply air temperature sensor; 12. Air filter; 13. Lambda probe; 14. Fuel pressure regulator; 15. Injector; 16. Pressure damper; 17. Cold engine start injector; 18. Idle air control valve (extra air); 19. Fuel system control switch; 20. Throttle position sensor; 21. Cold engine start injector timing relay; 22. Coolant temperature switch; 23. Starter; 24. Main relay; 25. Electrical circuit disconnect relay; 26. Speed sensor; 27. To the brake lights; 28. Headlight switch; 29. Rear window heating switch; 30. Electronic control unit; 31. Neutral switch sensor