Operation CHARM: Car repair manuals for everyone.

Fuel Delivery and Air Induction: Testing and Inspection

11 61 730 Check BMW diagnosis system for excess pressure and vacuum (N63).





Important!
Excess pressure and vacuum lines are identified by the size of the connection fittings and color-coded red and blue and must not be mixed up with each other.
Build up pressure with Blue color.
Generate vacuum pressure with Red color.
Mixing up the functions will result in damage to the engine.





Necessary preliminary work:
^ Release upper section of intake air filter.
^ Prepare BMW diagnosis system.
^ Start diagnostic program.
1. Power train
2. Engine electronics
3. Air supply
4. Charging pressure control
Oder Perception
Lack of power

Note on ordering:
- Workshop equipment.
- Workshop planning.
- Workshop equipment catalogue.
- Measuring and test equipment.
- No. 81 29 0 426 464





Pressure measurement:
Prepare BMW diagnosis system on excess pressure diagnosis unit.
1. Screw in pressure sensor.
2. Overpressure connection (Blue).
3. Connect stimuli cables (3) to positive and negative.
4. Connect 12V battery cables (4) to vehicle battery positive and negative.





Secure seal plug (1) with union nut (2) in intake port and seal.

Note:
Twin-Turbo: both intake ports must be sealed.

Insert Blue pneumatic hose (4) in pneumatic coupling (2) of sealing plug (1).

Seal plug (3) has no pneumatic coupling.








Vacuum pressure measurement:
Prepare diagnosis tester on vacuum diagnosis unit.
1. Screw in pressure sensor.
2. Connect stimuli cables (2) to positive and negative.
3. Connect 12V battery cables (3) to vehicle battery positive and negative.
4. Controller for vacuum connection.
5. Vacuum connection (Red).





Calibration for vacuum pressure measurement:
Seal shutoff tap (2) in direction of arrow.

Release lock nut on controller (1).

Carry out pressure adjustment in accordance with BMW diagnosis instruction.

Secure controller (1) hand-tight against turning.

Open shutoff tap (2) again.

Connections on EPPC:





1 Connection (VAC) to vacuum reservoir.

2 Connection (OUT) with ring to exhaust turbocharger.





Vacuum activation, cylinders 1-4.
Detach red vacuum line from vacuum unit.

Prepare T-piece (5) with vacuum lines for measurement.

Connect red vacuum line (1) with vacuum unit (2) and quick-release coupling (3).

Open shutoff tap (4).

Note:
Observe diagnosis instructions.





Vacuum activation, cylinders 5-8.
Detach blue vacuum line from vacuum unit.

Prepare T-piece (5) with vacuum lines for measurement.

Connect blue vacuum line (1) with vacuum unit (2) and quick-release coupling (3).

Open shutoff tap (4).

Note:
Observe diagnosis instructions.





Exhaust turbocharger, cylinders 1-4.
Initial position (1) of wastegate linkage depressurized.

Wastegate valve opened.





Initial position (1) of wastegate linkage with vacuum pressure.

Wastegate valve closed.





Exhaust turbocharger, cylinders 5-8.
Initial position (1) of wastegate linkage depressurized.

Wastegate valve opened.

Initial position (1) of wastegate linkage with vacuum pressure.





Wastegate valve closed.





Check wastegate valve with vacuum:
Wastegate valves must be opened without vacuum.

The wastegate valves must close if a vacuum pressure is applied at the wastegate sockets (see BMW diagnosis system).

Check shaft on turbine wheel for rotatability.





Follow diagnosis instructions.