New Generation N62 Engine
Chapter 4 P.17
Course Contents/Background Material
© BMW AG,
Service Training
- Variable intake manifold
General information
In the N62 engine, the infinitely variable intake manifold is
operated by turning the rotor in the intake manifold.
Adjustments to the intake manifold are carried out by a drive
unit. The drive unit consists of a 12 V DC electric motor with
worm gears and a potentiometer for the intake manifold position
bearing feedback.
The drive unit is equipped with a 5-pin connector.
Possible malfunctions/consequences
If the drive unit fails, the system remains in its current position.
The driver may notice this in the form of loss of power or
reduced elasticity.
- Idle speed control
The Valvetronic system controls the engine speed and the idle
speed.
Reduced valve lift when the engine is idling ensures that the
engine is allocated the appropriate airflow.
When the Valvetronic system is used, the idle speed control
must be adjusted. During the starting procedure and when the
engine is idling at a temperature of between -10 ºC and 60 ºC,
airflow is controlled by the throttle valve.
If the engine is at operating temperature, it will be switched to
non-throttle mode approximately 60 seconds after it is started
up. However, at temperatures below -10 ºC, the engine is started
with the throttle valve fully opened since this has a positive
effect on the starting characteristics.
