BMW 3 Series E46

since 1998 release

Repair and operation of the car



BMW 3 Series E46
+ BMW 3 cars (E46)
+ Current leaving and service
+ Engine
+ Cooling systems, heating
- Power supply systems, injection and release
   Security measures and rules of respect for purity during the work with fuel system
   Removal and installation of the sensor of a reserve of fuel / fuel pump
   Check of the sensor of a reserve of fuel
   + Power supply system of petrol engines
   + System of injection of fuel of the petrol engine
   + Power supply system of diesel engines
   - System of production of the fulfilled gases
      Operation of the catalytic converter
      Security measures for an exception of damages of the catalytic converter
      Turbocompressor
      Removal and installation of system of release
      Check of tightness of system of production of the fulfilled gases
      Removal and installation of the sensor of oxygen
      Removal and installation of a final collector
+ Engine electric equipment
+ RKPP and transmission line
+ Automatic transmission
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Schemes of electric equipment





Operation of the catalytic converter

Catalytic converter

1 — the case
2 — consolidation

3 — honeycombs of the catalytic converter


All engines are equipped with one or several catalytic converters for purification of exhaust gases.

The catalytic converter has the central ceramic part of a cellular design-3-covered with a carrier layer. On a layer of the carrier there are salts of precious metals operating as converters. The catalytic converter is fixed in the case-1-by means of the insulating basic layer-2-compensating at the same time thermal expansions of the catalytic converter.

To reduce harmful emissions by means of the catalytic converter, systems of injection has to dose precisely amount of the injectable fuel necessary for combustion. The sensor of oxygen is in a reception pipe in front of the catalytic converter and is washed by a stream of the fulfilled gases. The sensor of oxygen represents the electronic sensor measuring the content of oxygen in final gases and representing its type of fluctuations of tension. Information from the sensor of oxygen is transferred to the control unit of system of injection. The received value allows to regulate composition of air-petrol mix. On the one hand it is necessary as service conditions constantly change (idling, full gas), on the other hand, as optimum reburning of fuel in the catalytic converter happens only in this case if final gases contain enough fuel.

That in the catalytic converter there was a fuel reburning, it is necessary to have temperature of 300 - 800 °C. For this purpose the bigger content of fuel in mix, than is necessary for pure burning.

The used catalytic converters of petrol engines represent so-called three-functional devices. In adjustable process of transformation oxidation of carbon monoxide (SO) and hydrocarbon (NANOSECOND), and also reduction of concentration of nitrogen oxides (NOx) is carried out.