Pic. 15.14. Location of elements of the electronic engine control system without turbocharging: 1 - three-way electromagnetic distributor; 2 - control valve of the pressure regulator; 3 – atmospheric pressure sensor; 4 - three-way electromagnetic distributor; 5 - control unit; 6 - fuel pump relay; 7 - intake air temperature sensor; 8 - control air valve; 9 - main relay; 10 - air flow meter; 11 - temperature switch; 12 - analog coolant temperature sensor; 13 – oxygen concentration sensor; 14 - air valve; 15 - thermostat; 16 - control valve for exhaust gas recirculation; 17 - pneumatic shock absorber; 18 - recirculation valve with a smooth characteristic; 19 - throttle opening angle sensor; 20 - bypass solenoid valve
The EGI unit receives signals from a number of sensors that monitor parameters such as intake air volume, air and coolant temperature, engine speed, acceleration or braking mode, oxygen content in the exhaust gases. Based on this data, the microprocessor unit calculates the injection duration required to maintain the optimum air-fuel ratio. Some sensors and corresponding electromagnetic actuators controlled by the EGI unit are located in the engine compartment and are not part of the unit itself (pic. 15.14, 15.15).
Pic. 15.15. The location of the elements of the electronic control system of the turbocharged engine: 1 - self-unblocking relay of the fuel pump; 2 - control valve of the pressure regulator; 3 - three-way electromagnetic distributor; 4 - control unit; 5 - intake air temperature sensor; 6 - control air valve; 7 - main relay; 8 - air flow meter; 9 - analog coolant temperature sensor; 10 – temperature switch; 11 – oxygen concentration sensor; 12 - air valve; 13 - control valve for exhaust gas recirculation; 14 - position sensor for exhaust gas recirculation; 15 - reed valve body; 16 - pneumatic shock absorber; 17 - throttle assembly; 18 - solenoid recirculation valve; 19 - bypass solenoid valve; 20 - pressure switch; 21 - atmospheric pressure sensor
Attention! The power system is under pressure. Before disconnecting the elements of the power system, it is necessary to relieve the pressure in the system. To do this, cover the separation point with a clean rag and, being careful, slowly unscrew the union nut.
Warning! Gasoline is extremely flammable, when working with elements of the power system, the use of fire, sparking devices, open fire hazardous lighting devices, and smoking is prohibited. Sparks should be avoided when working with wires and electrical devices.