VOLKSWAGEN GOLF IV

since 1997 of release

Repair and car operation



Foltsvagen Golf 4
+ 1. Maintenance instruction
+ 2. Engine
+ 3. Cooling system
- 4. Fuel system
   - 4.1. Cars with petrol engines
      4.1.1. Removal and installation of the fuel pump / fuel level sensor
      4.1.2. Removal and installation of the fuel filter (petrol engines)
      4.1.3. Adjustment of a cable of an accelerator
      4.1.4. Removal and installation of the case of the air filter
      4.1.5. Remote check of elements of fuel system
      + 4.1.6. Check of the fuel pump
      4.1.7. Check of the relay of the fuel pump
      - 4.1.8. Control system of the engine
         4.1.8.1. Specifications
         4.1.8.2. Work of a control system as the engine
         4.1.8.3. Check of system of injection of fuel
         4.1.8.4. Sensors and executive mechanisms of a control system of the engine
         4.1.8.5. Fuel
         + 4.1.8.6. Ignition system
         4.1.8.7. Removal and installation of the fuel highway and nozzles
         4.1.8.8. Main malfunctions of a control system of the engine
   + 4.2. Cars with diesel engines
+ 5. Exhaust system
+ 6. Ventilation and heating system
+ 7. Coupling
+ 8. Transmission
+ 9. Suspension brackets and power shafts
+ 10. Steering
+ 11. Wheels and tires
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment and electroschemes










4.1.8.2. Work of a control system as the engine

GENERAL INFORMATION

Arrangement of the tape conductor in a measuring instrument of a stream of air

1–tape conductor

The control system of the engine is the incorporated system of ignition and fuel injection.

The fuel pump shipped in a fuel tank, submits fuel to the fuel highway via the fuel filter. Pressure of fuel in system copes a pressure regulator. The regulator allows excess of fuel to come back to a fuel tank at pressure excess in fuel system. The fuel highway is the tank for four fuel nozzles which make fuel injection to inlet canals of cylinders of the engine. The consecutive system of injection of fuel is used, at which nozzles inject fuel independently from each other. The control unit operates a fuel nozzle, changing width of an impulse, that is an interval of time, when the nozzle is open to provide richer or poorer fuel mix.

Air passes through the air filter, a measuring instrument of a stream of air and a butterfly valve to inlet channels of cylinders. The sensor of a stream of air represents the tape conductor (1) being energized. The constant temperature of a tape is supported by an electric current which changes depending on weight of passable air. The current which it is necessary to submit for maintenance of constant temperature of a tape, is proportional to mass of a stream of air. On the basis of information from a measuring instrument of a stream of air and other sensors the control unit regulates time and amount of injected fuel according to measured amount of air and number of turns of the engine. The nozzle is more long open, the more fuel is injected.

Additional sensors hand over information to the control unit about temperature of cooling liquid, temperature of air arriving in the engine, and on models with the catalyst – about the content of oxygen in exhaust gases.

The filter of absorbent carbon interferes with that harmful pairs of fuel got from a fuel tank into the atmosphere. Pairs of fuel collect in capacity with absorbent carbon and at operation of the engine дожигаются in engine cylinders.

The memory in the control unit distinguishes the appeared malfunction and writes down it. At failure of the important sensor the control unit is switched to the emergency program in order that the engine continued to work, though with smaller efficiency.