The power supply system of petrol engines

The general information

All models considered in the present Management are equipped by electronic system of the distributed injection of fuel (SFI). At the expense of use in a control system of the newest technological decisions SFI provides optimisation of configuration of an air-fuel mix at any service conditions of the engine.

Fuel is in the power supply system under constant pressure and through injectors is injected into inlet ports of each of engine cylinders. The dosage of giving of fuel is carried out by management of time of opening of electromagnetic valves of injectors according to the quantity of air forced in the engine defined by concrete operating conditions. Duration of opening of injectors is defined by parametres formed by the management module (ECM) electric impulses that allows to carry out rather exact dosage of components of a gas mixture.

ECM defines demanded duration of time of opening of injectors on the basis of the analysis of data continuously arriving from information gauges about quantity of air soaked up in the engine - термоанемометрический the gauge of measurement of weight of air (MAF), current turns of the engine - the gauge of position of a cranked shaft (CKP), and position throttle заслонок - TPS.

Besides the listed functions the system of the distributed injection of fuel carries out also the control of toxicity of the fulfilled gases, optimisation of a parity the expense of fuel/efficiency of return of the engine, and also provides adequate starting parametres and engine warming up in cold weather, proceeding from the data about temperatures of a cooling liquid (gauge ECT) and soaked up air (gauge IAT).

System of giving of air

Inlet air path

The inlet air path consists of an air inlet, two резонаторных chambers, assemblage of an air cleaner and connecting it with the case of a throttle an air line. The first resonator is located above an air cleaner on a stream, by means of a by-pass hose is connected to a back part of an air inlet and effectively promotes decrease in level of the noise background arising at всасывании of air in the engine. The second резонаторная the chamber is connected to an air line of an inlet air path directly ahead of the throttle case.

Design of an inlet air path of the petrol engine

Air banished through an air cleaner arrives in the throttle case, whence, in defined by position throttle заслонок (gauge TPS) quantity, on the inlet pipeline moves to inlet ports of cylinders of the engine where mixes up with fuel injected through injectors, forming a gas mixture. Stability of turns of idling is provided for the account перепускания parts of air weight bypassing the throttle case directly in the inlet pipeline. The control of quantity of restarted up air is carried out ECM by means of management of functioning special перепускного the valve of stabilisation of turns of idling (IAC).

The gauge of temperature of soaked up air (IAT)

Gauge IAT is established on assemblage of an air cleaner and serves for measurement of temperature of air soaked up in the engine. In a basis of a design of the gauge it is put термистор, which resistance in inverse proportion to temperature of a sensitive element. Parametres traced by the gauge will be transformed to electric signals and transferred on ECM, exercised administration of configuration of an air-fuel mix, and also the injection and ignition moments.

The gauge of measurement of weight of air (MAF)

Thermoanemometrichesky gauge MAF is established in an inlet air path directly behind an air cleaner and represents itself as the source of the information delivering ECM the data about quantity of air soaked up in the engine. On the basis of the analysis of information ECM arriving from the gauge carries out configuration of an air-fuel mix.

The throttle case

Placed in the throttle case заслонки cope from a gas pedal according to which position, to a greater or lesser extent block throttle apertures through passage that allows to regulate the expense of combustion of the engine of air arriving in chambers. On single turns when the gas pedal is completely released, заслонки almost completely block the throttle and air great bulk (more than half) arrives in the inlet pipeline through the special electromagnetic valve of stabilisation of turns of idling (IAC) bypassing the throttle case. Valve IAC use allows to carry out also the control of stability of turns of idling without dependence from changes of current loading on the engine (for example, at inclusion of the conditioner of air or other power-intensive consumers).

Design of the case of a throttle

The gauge of position throttle заслонок (TPS)

TPS it is established on the case of a throttle and it is mechanically connected to an axis throttle заслонок. The gauge develops and sends ECM the alarm pressure which size is directly proportional to opening degree заслонок. To the closed and opened positions заслонок there correspond accurately certain values of pressure.

The electromagnetic valve of stabilisation of turns of idling (IAC)

Valve IAC is included in an inlet air path ahead of the case of a throttle and exercises administration in size of the expense of air which is restarted up bypassing last at work of the engine on single turns. The valve works on signals ECM, allowing the last to support turns of idling of the engine at the set level.

Valve IAC design

System of giving of fuel

The general data

Placed in a petrol tank погружной the fuel pump provides fuel giving under pressure to each of injectors of a fuel highway. Gasoline moves from the pump to injectors on a fuel path with the filter of thin clearing included in it. The special regulator supports pressure of fuel in a highway on the set optimum level. Through injectors fuel in necessary quantity is injected directly into chambers of combustion of each of engine cylinders where mixes up with air and forms a gas mixture. The quantity of fuel and the injection moment are calculated by the management module. Surplus of fuel on a returnable line arrives back in a fuel tank.

The scheme of the organisation of system of giving of fuel

Fuel tank

The fuel tank made of a stamped steel in volume of 60 l is established under the car, directly ahead of the back bridge under assemblage of a back seat.

The tank is equipped by a filter protecting it from blows by stones, and fastens under the bottom of the car by means of five bolts.

The configuration of working volume of a tank is chosen so that топливозаборник a gasoline pump remained in the shipped position at any level of filling of a tank, even during sharp maneuvering.

The special unilateral valve preventing penetration of fuel from working volume of a tank back in a mouth at movement on impassability and sharp maneuvering is built in a jellied mouth of a tank.

Remember that correct (before operation of a rattle of a ratchet) the tightening of a cover of a jellied mouth is a guarantee of maintenance of demanded superfluous pressure in a fuel path.

Do not forget to exhaust from time to time the car on a platform and attentively to examine a fuel tank and the lines brought to it about revealing of mechanical damages.

The fuel pump

The fuel pump is united in uniform assemblage with the gauge of a stock of fuel. The pump has роторную a design and is placed in a fuel tank that allows in an essential measure to lower level made by it at work of a noise background.

Management of functioning of the fuel pump carries out ECM. At development by the module of management of a corresponding command there is an activation of the relay of the fuel pump then the electromotor starts to rotate, actuating a rotor of pump assemblage. Sucked in through the mesh filter топливозаборника fuel on connecting lines arrives in a fuel highway and under a pressure moves on injectors. The pumped pressure in a fuel path is supported at constant level by means of a special regulator. For the purpose of prevention of pressure drop of fuel at gasoline pump switching-off in pump assemblage it is included special запорный the valve.

Surplus of fuel on a returnable line is taken away back in a fuel tank.

Regulator of pressure of fuel

The pressure regulator is established from the end of a line of giving of fuel brought to injectors and consists of two chambers divided by a diaphragm: fuel and spring. The fuel chamber is connected to a line of giving of fuel, spring - with the inlet pipeline. At increase in depth of depression in the inlet pipeline diaphragm procrastination leads to opening brought to the fuel chamber of a regulator of a returnable line, - as a result pressure in a fuel highway decreases. Decrease in depth of depression in the pipeline leads отжиманию diaphragms a spring and to increase in submitting pressure. The described mechanism allows to support a difference between pressure of injection and depression in the inlet pipeline at the constant level making 290 кПа.

Fuel injectors

In system of the distributed injection injectors with the top giving of fuel are used. The scheme of connection of injectors provides cooling by their stream of fuel. Injectors of such design differ in the compact sizes, the high thermal stability, the lowered noise background and simplicity in service.

Duration of opening of the electromagnetic needle valve of an injector is defined in the length developed ECM an operating impulse. Whereas the section of a nozzle of an injector, size of opening of the valve and pressure of giving of fuel are supported by constants, the quantity of combustion of fuel injected into the chamber is defined exclusively by duration of time of the opening corresponding to length of the operating impulse.

The gauge of a stock of fuel

The gauge is united in uniform assemblage with the fuel pump and consists of the float fixed on the lever and a potentiometer.

Change of level of fuel is traced by a potentiometer by the float position, the corresponding indication is deduced on built in in a combination of devices a measuring instrument.

Connecting lines of a fuel path

Giving of fuel from a gasoline pump to a fuel highway and its return to a fuel tank is carried out on metal by tubes and to hoses of lines of giving and fuel return. Lines by means of clamps fasten to the car bottom. Also should be checked regularly on presence of mechanical damages.

Besides submitting and returnable gasoline pipe lines it is necessary to carry to number of connecting lines of a path of the power supply system also lines of tap of fuel evaporations on which accumulating in a fuel tank during parking of pair fuel are taken away in a special coal adsorber located in an impellent compartment. At squeezing of a pedal of gas after warming up of the engine to normal working temperature at the command of ECM the purge of an adsorber with a conclusion of the fuel which has accumulated in it in the inlet pipeline with its subsequent burning in a normal running cycle of the engine is carried out.

The filter of thin clearing

The filter of thin clearing is included in structure of a line of giving of fuel.

The case of the fuel filter is capable to maintain high enough temperature, vibrating and shock loadings. In the case the paper filtering element providing clearing of fuel submitted to a fuel highway from extraneous particles, not caught by a grid топливозаборника a gasoline pump and capable to put out of action injectors is enclosed.

Recommendations about economy of the expense of fuel

Essential influence on the fuel expense renders style of driving of the car. Resulted below the recommendation will allow the owner to achieve economy of the expense of fuel at reception of adequate return from the engine.

Try to avoid long warmings up of the engine, - begin movement at once as soon as turns are stabilised; At a car stop for a while more for 40 seconds suppress the engine; Always try to move on as much as possible high transfer, avoiding sharp dispersals; On distant trips whenever possible try to move with uniform speed. Avoid movement on excessively high speeds. Operate the car circumspectly. Without need do not brake; Transport the car excessive cargo. If the top luggage carrier is not used, remove it from a roof; Regularly check pressure of a rating of tyres, without supposing its excessive decrease.