BMW 3 series E30

Since 1983-1994 of release

Repair and car operation

6.1. Introduction

THE GENERAL DATA

Considered cars are equipped by system of injection of fuel, except models 316 on which carburettors Solex 2B4 (cars of early release) and Solex 2BЕ (later release are established). The fuel pump of carburettor engines mechanical, with кулачковым a drive from a cam-shaft.

System of injection of type L-Jetronic or Motronic. Since 1988 cars are equipped with advanced system Motronic in which there is no atomizer for start-up of the cold engine. The electric fuel pump is mounted or in a back part of the car, on the body bottom (on early models), or in a fuel tank. In system Motronic of the relay of injection works from a signal from the block of management (ECU-block). At ignition inclusion the fuel pump works within several seconds and is disconnected only after a full stop of the engine. On early models the pump of pumping of the low pressure, mounted in a fuel tank and included consistently with the basic pump is provided. The basic pump provides maintenance of necessary pressure of fuel. Maintenance of constant pressure at the moment of injection is provided with a regulator of pressure and a suppressor of pulsations of pressure (last is mounted about the fuel filter).

The system of injection of fuel of considered cars consists of 3 subsystems – fuel, a fence of air and the processor block of management.

Fuel system

The fuel pump provides fuel giving through the filter in the distributor under constant pressure. Stabilisation of pressure of fuel on a distributor exit is provided with a pressure regulator.

System of a fence of air

Consists of an air cleaner, a measuring instrument of a stream of air, the throttle branch pipe, a soaking up collector and connecting hoses and branch pipes. The measuring instrument of a stream of air лопастного type, air expense is proportional to an angle of rotation заслонки and to resistance of the potentiometer, rigidly connected with an axis заслонки.

The electronic block of management

On the car the electronic block of management (ECU) which provides automatic adjustment of the moment of ignition and also quantity and structure mix fuel-air according to the information from the various gauges tracing power setting is established. The structure of auxiliary elements of system (gauges, switches, etc.) is defined by a concrete kind of applied system of injection.

Applied systems of injection

System of injection of type L-Jetronic of firm Bosch (till 1987)

System of injection L-Jetronic

1. A fuel tank 2. Рапределитель fuel 3. A pressure regulator 4. The processor block 5. The relay 6. A measuring instrument of speed of a stream 7. The ignition switch 8. The battery 9. Throttle заслонка 10. The switch throttle заслонки

11. The valve of start of the cold engine 12. The proof-reader of idling 13. The ignition distributor 14. A thermotimer 15. The gauge of temperature of the engine 16. The oxygen gauge 17. An atomizer 18. Fuel фильт 19. The fuel pump

System однофорсуночная with an electromagnetic atomizer. The core in adjustable parametres are duration of an open condition of atomizers (quantity of injected fuel) and idling turns. Auxiliary elements of system are the gauge of temperature of a cooling liquid, the switch throttle заслонки, the idling stabilizer (перепускной the air valve), the relay and safety locks.

System of injection of type Motronic

System of injection Motronic

1. A fuel tank 2. The processor block 3. Гаситель pulsations 4. A regulator of pressure of fuel 5. The valve of start of the cold engine 6. The switch throttle заслонки 7. A measuring instrument of speed of a stream 8. The proof-reader of idling 9. The relay of the fuel pump 10. The main relay 11. The ignition switch 12. The battery 13. The gauge of an angle of rotation коленвала

14. Throttle заслонка 15. The gauge of speed of rotation коленвала 16. The gauge of temperature of the engine 17. A thermotimer 18. The oxygen gauge 19. The ignition coil 20. A candle 21. An atomizer 22. The ignition distributor 23. The fuel pump 24. The fuel filter 25. The fuel distributor

System многофорсуночная with electromagnetic atomizers. Adjustable parametres are the quantity of injected fuel, the ignition moment, turns of idling and structure of exhaust gases.