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Engine mechanical system
Basic position
Engine off
No oil pressure is available when the engine is
switched off. The spring-loaded locking pin is pressed
into the adjustment piston's detent groove, locking it.
Starting the engine
When the engine is started, the oil pressure is not yet
sufficient to press the locking pin out of the adjustment
piston's detent groove.
The locking function and the oil reservoir chamber in the camshaft adjustment unit reduce vibrations in
the chain drive. Noise during the starting phase is minimised as a result of this.
Basic position: From idle speed to approx. 1000 rpm
Torque position: From approx. 1000 rpm to approx. 3600 rpm in the Touareg and approx. 5600 rpm
in the Phaeton
Output position: From approx. 3600 rpm in the Touareg and approx. 5600 rpm in the Phaeton
How it works:
Depending on the manner in which the camshaft adjustment valve is actuated, the oil is guided into two
different control ports. The ports are linked to the chambers on both sides of the adjustment piston.
Adjustment in the "retard" direction takes place via port A, whilst adjustment in the "advance" direction occurs via
port B.
Control ports
S341_034
Adjustment piston
Oil reservoir chamber
Locking pin
Lubrication and
breather bore
