Audi A4

Since 1994 of release

Repair and car operation



Audi А4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ Exhaust system
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and channels всасывания
- Injection system
   - System of injection Motronic
      The major knots
      So the system of injection Motronic functions
      Infringements in work and self-diagnostics
      The self-help at injection
      The visual control
      Search of malfunctions in separate knots
      Check of idling and the fulfilled gases
      Check of the fulfilled gases (AU)
      Cable throttle заслонки
      The help at malfunctions
   + System of injection MPI and MPFI
+ Coupling
+ Transmission and the main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tyres
+ The electrotechnical equipment
+ Ignition system
+ Illumination
+ The alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics
элитные проститутки питера



The major knots

The electronic block of management

The management block in an electronic box through многоштырьковый a socket receives the information:

  • Starter, the plug of 50 beginnings and end of process of start-up;
  • Potentiometer throttle заслонки, its positions at present;
  • The gauge of the Hall of system of ignition for adjustment of number of turns of the engine;
  • Ljambda-probe in каталитическом the converter for measurement of the maintenance of residual oxygen in the fulfilled gases;
  • Measuring instrument of a stream of soaked up air;
  • The gauge of temperature of soaked up air (only in турбодвигателе capacity of 110 kw);
  • The gauge of temperature of a cooling liquid in a tube of giving of a cooling liquid behind a head of the block of cylinders;
  • Sensor control of a detonation I on the engine block at "detonation" combustion;
  • Sensor control of a detonation II (only in engines with working volume 1,8) also on the block of the engine for exact localisation of detonation combustion.

On the basis of the information on number of turns and pressure in an inlet collector the management block counts duration of opening of the injectors put in action by an electromagnetic way, and, accordingly, quantity of injected fuel. For this purpose in the order of the block of management the characteristics of the engine representing meeting of the data about all conceivable situations of the engine, about quantity of fuel necessary for everyone situation and the corresponding moment of ignition are given. The management block can vary still characteristics after receipt of so-called correcting signals (for example, temperature of soaked up air and a cooling liquid).

The block of management throttle заслонкой

The block of management (2) systems of ignition/injection is in an electronic box at the left behind in an impellent compartment (in the so-called humidifying tank). In an arm (1) near to the management block there is a place of the gauge of height for турбодвигателя.


The block of management throttle заслонкой in турбодвигателе with working volume 1,8 l: 1 – the lever throttle заслонки; 2 – knot of connection of power supplies of the block of management (3) throttle заслонкой; 4 – throttle заслонка.


The block of management throttle заслонкой in the engine with working volume 1,6 l basically is identical to the block of the engine with working volume 1,8 l, though assembly position at it another. By figures are designated: 1 – connection knot to power supplies; 2 – the lever throttle заслонки.

In the so-called block of management throttle заслонкой three separate knots known on other systems of injection as functional blocks are united.

Throttle заслонка. It is connected by a cable with a pedal in salon and doses out a stream of fresh air in the engine. The the gas pedal is more pressed, the opens throttle заслонка more strongly, at full gas it is opened completely.

Potentiometer throttle заслонки. The potentiometer throttle заслонки defines position throttle заслонки on given the moment in a range from idling (throttle заслонка it is closed) to full gas (throttle заслонка is opened completely). On the basis of its information the valve of stabilisation of the idling, also integrated in a branch pipe throttle заслонки becomes more active, there is a switching-off of draught or mix enrichment at full loading.

The valve of stabilisation of idling. It lets in the dosed out additional quantity of air channels всасывания for throttle заслонкой at a stage of warming up of the engine, at full turn сервоуправления, at working climatic installation or the established step of automatic transfer. The raised stream of air in a direction of the soaking up pipeline is distinguished by a measuring instrument of a stream of fresh air and as consequence causes the raised giving of fuel. Thus, there is a decrease in the raised friction in not heated-up engine or at the raised loading on the engine for the account сервонасоса, the compressor of climatic installation or automatic transfer which take away capacity from the engine.

Pressure regulator

The regulator of pressure (1) fuels is connected to a branch pipe throttle заслонки by means of a vacuum hose (2). It regulates pressure in system by increase or fall recycling fuel.

It is in the distributor of fuel and regulates its pressure upon injectors. For this purpose the information on level of the lowered pressure in an inlet collector is transferred to it. Idling at closed throttle заслонке and very low pressure it holds lower pressure. With pressure drop at the raised loading on the engine the pressure regulator raises pressure of fuel. The fuel pump creates much higher operational pressure, but by means of a regulator of pressure return of gasoline to a fuel tank accordingly increases or decreases.

Injection valves

Valves of injection (4–7) settle down in the direction of travel on a left-hand side of a head of the block of cylinders in an inlet collector. Further by figures are designated: 1 – a regulator of pressure of fuel; 2 – a submitting gasoline pipe line; 3 – a distributive tube of fuel.


On this model in a cut it is visible that each valve of injection (3) makes injection in soaking up pipe (4). Fuel arrives to it from a distributive tube (1), signals for injection go through cable connection (2) to the management block.

At each turn коленвала they inject gasoline into the channel всасывания in front of the inlet valve of the corresponding cylinder – duration is defined by the management block.

The gauge of temperature of soaked up air

At турбодвигателе capacity of 110 kw it is in воздухозаборном a hose and can precisely take temperature of air submitted турбокомпрессором. The information on temperature arrives in the block of management in the form of resistance size. It is used for an optimum dosage of fuel. Hot турбокомпрессор depending on a working condition strongly heats up soaked up air.

The gauge of temperature of a cooling liquid

The temperature of a cooling liquid is used at management of several functions of injection: at enrichment of a toplivno-air mix during start of the cold engine, послестартового enrichments (on all range of temperatures), at enrichment during accelerations and draught switching-off. The information on temperature of a cooling liquid is transferred in the management block also in the form of resistance size. He counts correct time of injection which in the heated-up engine makes from 2 to 8 мс. This size can increase almost on 70 % when the temperature goes down to the Arctic level–25 °С.

Measuring instrument of a stream of fresh air

In a stream of soaked up air there is an electrospending plate which is warmed up in the electroway. Depending on quantity of soaked up air its stream which cools a plate more strongly or more poorly varies. Temperature change causes change of electric resistance of a conductor. This measured size is used by the management block.

Behind on the right безнаддувного the engine with working volume 1,6 and 1,8 l are in an impellent compartment a measuring instrument of a stream of fresh air (1), прифланцованный to the case of the air filter. By figure "2" the connection socket is shown. In турбодвигателе with working volume 1,8 l the measuring instrument of a stream of fresh air settles down inside in the case of the air filter.