Variable Valve Timing Actuator: Testing and Inspection

Crank engine in direction of rotation until cam peaks of intake and exhaust cams in cylinder No.1 face each other.







Hold crankshaft in TDC position with Special Tool 11 2300.


CAUTION! Do not turn the engine back.
Remove special tool prior to operating engine.







Unscrew oil pipe at VANOS control unit.

Installation:
Check sealing rings, replacing if necessary.






Fit special tool 11 3 450 with banjo bolt.
Connect to air pressure supply (2... 8 bar).







Measure gap between secondary tensioner and edge on the sensor gear.
Note the value.







Connect special tool 12 6 410 to 4/2-way valve for VANOS.
Connect battery.
Ensure that poles are not mixed up.
Camshaft will be adjusted in advanced direction.







Measure gap between secondary tensioner and edge on the sensor gear.
Note the value.
The difference between both measured values must be at least 8.5 mm.