- Repeated malfunctions following installation of a new servo motor
- Fluctuations in speed and jerking
- Diagnostic trouble codes P1018, P208, P2011, P3135
DO NOT FORGET TEACHING-IN!
Electric servo motors (01) ensure the fast and precise adjustment of flaps (04) on or in the intake manifold. These flaps may be: swirl flaps (inlet port shut-off), tumble flaps, resonance flaps, variable length control.
When such a component has been replaced, the control unit often has to be informed that a new part has been installed for which the old data no longer applies.
This teaching-in process generally occurs via the applicable program option in the menu of the engine tester. When this function is carried out, the actuator moves to the end stops and the control unit saves this data.
Other names are: actuator and drive module
Flaps are dirty or blocked
If the flaps (04) are carbonised or stuck, or blocked completely, then the mechanical resistance to move them increases. This may be detected as a fault, but only the actuator is listed as the cause in the fault code memory.
Flap bearing faulty
The bearing positions of the shaft (03) on which the flaps turn may be worn out.
Condition of the link rod
The link rod (02) between the actuator (01) and the adjusting lever of the flaps may be faulty. The following damage is possible: Spherical head is worn out; rod has play; rod is bent. In this case, too, it is only the actuator that is mentioned in the fault code memory.
In all of these cases, the only thing that often helps is the additional replacement of the intake manifold.