Irregular or rough running is when rotation that is out of shape occurs in the work process of the motion of the crankshaft drive and flywheel mass. A fluctuation in the smooth running of diesel engines can be caused by a fluctuating mean engine speed, tolerances in the fuel injection due to the operating mode, and by errors in the adaptations of the function software. The causes are frequently problems in the glow system, problems with inadequate compression, tolerance in the fuel injection rates or other causes that can lead to combustion misfires. The smooth running control is a pure software functionality mapped in the diesel engine management system:
With the smooth running control, the DDE control unit performs the task of detecting differences in torque due to different cylinder compression, cylinder friction, tolerances in the hydraulic injection components as well as other causes due to the resulting fluctuating mean speed and to balance these out with specific adaptations of the fuel injection rate of the cylinder concerned.
This is implemented via complex software-internal control technology models.