CDI smooth running control - function - GF07.16-P-3018IC

ENGINE 647.961 in MODEL 211 

ENGINE 648.960 in MODEL 220 

ENGINE 648.961 in MODEL 211 

Fig 1: CDI Smooth Running Control Function Chart

Smooth running control reduces irregular engine running at idle speeds.

For the smooth engine running analysis the signal supplied by the crankshaft position sensor is analyzed exactly in respect of time uniformity between the individual combustions by means of a comprehensive mathematical method.

Each individual combustion must produce a characteristic acceleration at the flywheel.

In the event of combustion misfires, rotation of the flywheel mass is slightly slower for a short time (short torque fluctuation).

The following conditions must be in effect for smooth running control:

• Engine speed <1200 rpm
• Engine at idle speed
• Sensor rotor adaptation completed (crankshaft position sensor)

Drops in engine running speed are compensated for by the CDI control unit over cylinder-specific fuel injection quantities. Idling speed remains constant as a result.

Sensor adaptation 

After sensor adaptation is performed, the smooth engine running analysis becomes more sensitive and can be adapted to the specific smooth running properties of the engine.

In the overrun (uniform smooth operation) the special smooth running characteristics of the engine are stored for smooth running analysis.