Opel Astra, Zafira

Since 1998 of release

Repair and car operation

Systems of injection and turbo-supercharging of the diesel engine

The general information

At work of the diesel engine in its cylinders pure air which is compressed to a high pressure is soaked up. Thus air temperature rises to 700 - 900°С that exceeds temperature of ignition of diesel fuel. Fuel is injected into the cylinder with some advancing and ignites. Thus, spark plugs for fuel ignition are not used.

Fuel is sucked in by the fuel pump of a high pressure (Fuel pump) directly from a tank. In Fuel pump fuel is compressed to pressure necessary for injection. Injection is carried out in an order similar to an order of ignition in the petrol engine.

At the approach of a stock of fuel by the end, - on the panel of devices the alarm lamp lights up, - it is necessary to make car refuelling immediately.

For the purpose of decrease in toxicity of the fulfilled gases in a standard complete set of all diesel models joins каталитический the converter. Simultaneously the system рециркуляции provides essential decrease in the maintenance in the fulfilled gases of oxides of nitrogen, the part of the fulfilled gases is mixed to air soaked up in the engine that provides concentration decrease in it of oxygen and, accordingly, to reduction of a delay of ignition and fall of temperature of combustion. Result of all listed processes is formation minimisation in products of combustion of oxides of nitrogen (NОХ). Process рециркуляции the fulfilled gases demands an exact dosage, maintenance level otherwise increases in products of combustion of coal particles (soot). The dosage is carried out at the expense of inclusion in a chain of system of a special measuring instrument, - the information arriving from a measuring instrument allows the electronic module to operate process рециркуляции.

On engines of 1.7 l SOHC fuel injection is made in форкамеры cylinders, on engines of 1.7 l DOHC and 2.0 l - is direct in combustion chambers.

Fuel pump has electronic control that guarantees conformity to rigid modern requirements under the maintenance in the fulfilled gases of the engine of toxic components. A control system brain is the electronic module built in pump assemblage continuously analyzing the data, arriving from the whole complex of information gauges:

Engines of 1.7 l SOHC

• The gauge of position of a pedal of an accelerator informs management blocks on position of a pedal of gas;
• The gauge of temperature of a cooling liquid (ECT) informs management blocks on working temperature of the engine;
• The gauge of a measuring instrument of weight of air (MAF) informs management blocks on weight and temperature of air soaked up in an inlet air line;
• The gauge of position of a cranked shaft (CKP) informs management blocks on position and speed of rotation of a cranked shaft;
• The gauge of pressure of pressurisation informs management blocks on pressure in the inlet pipeline;
• Gauges and regulators Fuel pump (built in) are used by management blocks at calculation and management of the moments and quantity of fuel injected into the engine;
• The coupling gauge is used by management blocks at performance of functions tempostatа;
• The gauge-switch of activation К/В informs management blocks on inclusion or deenergizing of the conditioner of air.

Engines of 1.7 l DOHC and 2.0 l

• The gauge of position of a pedal of an accelerator informs management blocks on position of a pedal of gas;
• The gauge of temperature of a cooling liquid (ECT) informs management blocks on working temperature of the engine;
• The gauge of temperature of soaked up air (IAT) informs management blocks on air temperature in an inlet air line;
• The gauge of a measuring instrument of weight of air (MAF) informs management blocks on weight of air passing through an inlet air line;
• The gauge of temperature of oil (engines 2.0) informs management blocks on temperature of impellent oil;
• The gauge of position of a cranked shaft (CKP) informs management blocks on position and speed of rotation of a cranked shaft;
• The gauge of pressure of pressurisation informs management blocks on pressure in the inlet pipeline;
• The module of management ABS informs management blocks on speed of movement of the car;
• The gauge of atmospheric pressure (BARO) informs management blocks on atmospheric pressure;
• The gauge of temperature of fuel informs management blocks on fuel temperature;
• The position gauge bringing down Fuel pump it is used by management blocks at calculation and installation of the moments of injection of fuel;
• The gauge of emergency pressure of oil is used ECM the engine at management of operation of a control lamp on the panel of devices;
• The coupling gauge is used by management blocks at performance of functions tempostatа;
• The gauge-switch of activation К/В informs management blocks on inclusion or deenergizing of the conditioner of air.

All data arriving from information gauges is processed by the electronic blocks of management exercising on the basis of its analysis administration by the moments and quantity of injection of fuel, providing optimum operational characteristics of the power unit without dependence from change of external factors. ECM the engine operates the injection moment through the block of management Fuel pump, providing reliability of start of the engine at any temperature of air, its prompt warming up, and also the maximum return in all modes of movement, including an acceleration and braking by the engine.

Base installation of the moments of injection is made at installation Fuel pump on the engine. In the course of functioning of the unit of change of the given characteristic occurs automatically on commands ECM means кулачкового the executive mechanism.

The dosage of fuel submitted to the engine is made by means of built in in Fuel pump valves of quantity and the injection moment. Operation of valves occurs on the commands which are given out by the block of management Fuel pump, usually located in the top part of the pump. On the main rotor Fuel pump the special ring is established. The gauge of position of a rotor defines position and speed of rotation of a rotor. The gauge works by a principle similar to a principle of work of the gauge of position of a cranked shaft. On a rotor it is put four labels - according to quantity of cylinders. The block of management of the pump receives the necessary information from the engine management block (ECM) and counts the moments and duration of giving of fuel. Internal components Fuel pump allow to count very precisely these parametres that finally leads to increase of efficiency of return of the engine and decrease in toxicity of the fulfilled gases.

On diesel models is absent a gas cable, - its functions are carried out by the gauge of position of a pedal of an accelerator. The gauge continuously informs the management block on pedal position that allows ECM to count injection parametres precisely. Idling turns also are regulated by the block of management and to manual updating are not subject. Analyzing the information arriving from various gauges, the management block counts quantity of turns, correcting them depending on loading and engine temperature.

The pump incorporates to atomizers metal tubes. Each atomizer submits fuel to combustion chambers through five apertures. It reaches uniform distribution of fuel in the chamber of combustion and an exact direction of giving of fuel. The system of injection of fuel is system of direct injection. In the bottoms of pistons there are the vortical chambers providing a turbulence of combustion arriving in chambers of fuel. For optimisation of combustion of fuel of an atomizer open in two stages (for this purpose in each atomizer there are two springs). At atomizer opening the small part of fuel gets on internal components of an atomizer, greasing them, and comes back in a fuel tank.

Management of warming up of the cold engine is carried out by the block of engine management and the block of management Fuel pump. At the cold engine the injection moment is displaced by the block of management Fuel pump. The engine management block, in turn, operates work of candles накаливания. Candles накаливания are established in each cylinder and join before engine start, working during time проворачивания the engine as a starter and some time after engine start. Candles considerably facilitate start of the cold engine. After ignition inclusion on a control panel the control lamp (the Operation manual see the Head), signalling about inclusion of candles накаливания lights up. As soon as the lamp will go out, it is possible to start realisation of start of the engine. At very cold weather of a candle continue to work still some time after engine start, providing stability of functioning of the last and decrease in level of the maintenance of toxic components in the fulfilled gases.

Owing to high starting qualities necessity for preliminary heat on models with direct injection of fuel is required only at temperature more low-10°S.

If from gauges the information testifying to occurrence of a supernumerary situation arrives, ECM is switched in functioning emergency operation when instead of inadequate signals base values of corresponding parametres are substituted, - efficiency of return of the engine in such mode, naturally decreases. About input ECM in emergency operation of the driver warns operation of a control lamp of refusals on an instrument guard of the car (the Operation manual see the Head), in memory of the processor the corresponding diagnostic code (the engine Electric equipment see the Head) is thus brought.

At operation of a control lamp the car should be driven away at the first possibility on firm car repair shop Opel for carrying out of detailed diagnostics with application of the special equipment and performance of necessary regenerative repair.