6.2.5.2. Models of 1,8 l
On early models 1,8 with the engine 18 E the system of injection of Bosch LE-Jetronic fuel was installed.
Due to electronic control the system of injection of fuel provides exact dispensing of fuel for effective operation of the engine with the minimum level of emission of harmful substances in the atmosphere. It is reached by constant control of operation of the engine various sensors which transfer information in the form of electric signals to the control unit (ECU). On the basis of these data the control unit defines amount of fuel which needs to be given to the engine on all operational modes and turns of the engine. The injection of fuel is made directly in an inlet collector.
On the basis of information from sensors the control unit regulates time and amount of injectable fuel. The amount of injectable fuel is proportional to duration of an open condition of a fuel nozzle to which for a certain time depending on an operating mode the electric signal is given. As a result of giving of tension on an electromagnet winding the anchor of a fuel nozzle is involved, the needle valve rises, thereby opening an injection opening, and fuel moves in an inlet collector about the inlet valve.
The relay of management contains an electronic element of an advancing and the relay switch which blocks supply of fuel after an engine stop.
The sensor of a stream of air measures amount of the air coming at present time to the engine. In the case of the measuring instrument of a stream of air there is a gate which when passing an air stream deviates. The corner of a deviation of the gate serves as an air stream measure. From a potentiometer on a gate axis the signals corresponding to position of the gate come to the control unit. The control unit regulates time and amount of injectable fuel according to the measured amount of air and speed of the engine. The longer the nozzle is open, the more fuel is injected.
Fuel nozzles represent the electromagnetic operated valves which open on control unit signals. Fuel nozzles receive only one boost opening them at the same time once for one turn of a bent shaft. The ECU block operates a fuel nozzle, changing the impulse width, that is an interval of time when the nozzle is open to provide richer or poorer fuel mix. The fuel pump – electric with the circulating camera, is placed in a back part of the car. The fuel pump gives fuel to the fuel highway which also performs functions of the tank for fuel nozzles. The amount of the fuel given by the pump considerably exceeds amount of the fuel consumed by the engine therefore continuous circulation of fuel in system is carried out. It allows to maintain fuel temperature at a low level and reduces probability of formation of traffic jams of steam in fuel system therefore start of the hot engine improves.
The fuel pressure regulator located in the fuel highway supports fuel pressure in fuel system at the certain level. The regulator of pressure of fuel consists of a metal casing in which the diaphragm dividing a casing into two cameras is established. Fuel comes to one camera of the regulator, and in another depression from an inlet collector moves. On a diaphragm the valve is rigidly fixed, at a deviation of a diaphragm the channel on which fuel comes back to the fuel tank opens. As a result of it at increase in depression in an inlet collector fuel pressure in fuel system in proportion decreases.
The sensor of provision of a butterfly valve is connected to an axis of a butterfly valve. The sensor defines the provision of a butterfly valve.
Information from the sensor of provision of a butterfly valve is used for reduction of supply of fuel when braking by the engine therefore fuel is saved and the content of harmful substances in exhaust gases decreases.
The additional air valve represents the air channel of big section which is connected by hoses to the case of a throttle and an inlet collector. The valve passes additional amount of air in the engine, passing a butterfly valve.
On the valve there is a gate connected to a bimetallic spring. On the cold engine the bimetallic plate takes away the gate, opening the additional air channel. In the course of warming up of the engine on the valve tension moves, the bimetallic plate heats up and, moving the gate, blocks supply of additional air in the engine. The amount of the additional air passing through the valve is measured by the measuring instrument of a stream of air on the basis of which information the fuel injection duration therefore at warming up of the engine the bigger amount of fuel-air mix comes to the engine is corrected.
For measurement of temperature two sensors are used. One sensor takes temperature to cooling liquid in the engine cooling system, the second sensor takes temperature of the air coming to the engine. Sensors represent resistors which resistance decreases at increase in temperature.