BMW 3 Series E30

since 1983-1994 release

Repair and operation of the car



BMW E30
+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engine
+ 4. Cooling system
+ 5. Heating and ventilation
- 6. Fuel system
   6.2. Specifications
   6.3. Check of system of injection
   6.4. Air stream measuring instrument
   6.5. Throttle branch pipe
   6.6. Fuel pressure regulator
   6.7. Nozzle of launch of the cold engine and thermotimer
   6.8. Check and replacement of nozzles
   6.9. Air proofreader of idling
   6.10. Order of a decompression of fuel system
   6.11. Check of pressure of fuel
   6.12. The fuel pump, the pump of pumping and the fuel level sensor in a tank
   6.13. Fuel pipes and union
   6.14. Fuel tank
   6.15. Air filter
   6.16. Cable of the drive of a butterfly valve
   6.17. Carburetor
+ 7. Exhaust system
+ 8. Transmissions
+ 9. Coupling
+ 10. Brake system
+ 11. Running gear
+ 12. Body
+ 13. Electric equipment
+ 14. Useful tips



6.4. Air stream measuring instrument

GENERAL INFORMATION

Air stream measuring instrument (L-Jetronic system)

1. Adjusting screw

2. Measuring instrument gate

Air stream measuring instrument (Motronic system)

1. Processor block
2. Measuring instrument gate
3. Butterfly valve
4. Stream measuring instrument
5. The sensor of temperature of the soaked-up air
6. Air cleaner

Check, removal, installation

PERFORMANCE ORDER
System of injection like L-Jetronic
1. Disconnect an air duct from the stream measuring instrument. Check freedom of the course of the gate. At backfires the gate of the measuring instrument can warp that leads to the wrong reading of resistance of a potentiometer and also to jamming of the gate. Traction qualities of the engine are as a result lost, and idling the engine becomes deaf.
2. Disconnect the socket from the stream measuring instrument.
3. Check resistance between conclusions 7 and 8 (in the drawing conclusions of the socket of the processor block are shown). In process of movement of the gate resistance has to change smoothly without jumps.
4. Check air temperature sensor resistance in the stream measuring instrument between conclusions 8 and 9. Resistance has to be 2200–2700 Ohms.
5. Check a chain from the measuring instrument to the processor block for what switch off ignition, attach the socket to the measuring instrument and disconnect the socket on the processor block (is under the forward panel of salon on the right). Check resistance between conclusions 7 and 8, moving the gate. If results of measurements differ, then malfunction of conducting is the reason.
System of injection like Motronic
6. Uncover the processor block, it is under the forward panel of salon on the right side of (the car with the left wheel).
7. Check measuring instrument potentiometer resistance between conclusions 7 and 9 (on early systems).
8. Check measuring instrument potentiometer resistance between conclusions 7 and 12 (on late systems). In process of movement of the gate resistance has to change smoothly without jumps.

Prevention

The socket of early systems 35-shtyrkovy, on the late Motronic system is installed the 55-shtyrkovy socket.


9. If resistance does not meet standard, then check conducting.

Removal and installation (all models)

PERFORMANCE ORDER
1. Disconnect the socket from the measuring instrument.
2. Remove the air cleaner. Take away latches and remove the air offtake located in the air cleaner case.
3. Turn off nuts and remove the stream measuring instrument.
4. Installation is carried out upside-down.