Document: MKB AKF, Vehicle vibrates (Solution)

The vehicle vibrates when stationary or jerks at engine speeds around 1500 RPM. The vibration is also noticeable between 60-85 km/h, and sometimes up to 130 km/h. There are no error codes stored in the system.

Affected vehicle identification numbers (VINs):
Up to 4D2N001843.

Cause:
Irregularities in the manufacturing of the speed sensor ring.

The spacing between the poles of the crankshaft position sensor is not uniform, which leads to incorrect information being sent to the idle speed control system. The idle speed control system then attempts to regulate a non-existent uneven engine running pattern. This can then lead to the problem mentioned above.


Solution;
Check the idle speed control in data blocks 13 and 14, both when stationary and while driving up to an engine speed of approximately 1400 RPM (above this speed, the idle speed control is no longer active). Also, please refer to the thread about rough idling and shaking at idle (related to aggregates, function, and faulty injectors). If a defective crankshaft position sensor is present, you will see four injectors in the negative range and four injectors in the positive range in data blocks 13 and 14. When considering the ignition sequence, an injector in the negative range alternates with an injector in the positive range during each firing cycle. If this is the case, the crankshaft position sensor must be replaced.