Air mass control, basic function: Diagnostics
In principle, the air mass/combustion is the same as engine torque. Air mass control is therefore of great interest when diagnosing bad performance.
There is a special menu in the diagnostic tool from which values of interest can be read. The most important is the deviation between requested and current air mass/combustion.
The current value should always, sometimes after a short interruption, follow the requested value. If this is not the case a fault in the turbo function is possible.
NOTE:
A fault in the throttle control can be eliminated because deviations between the present throttle position value and its desired value place the throttle control in limp-home.