reference valve no torque or speed change would result and no adaptation would occur the torque or the speed also changes only if the valve deviates from the reference valve because of tolerances or wear in the described case the torque and or the speed drops it is thus necessary to correct the slope of the characteristic curve upward the slope of the characteristic curve is expediently changed in that the characteristic curve is pivoted around the point of intersection of the reference characteristic curve and the adapted characteristic curve in fig2 this corresponds to an offset of the minimum activation energy in the ordinate axis in contrast if it is established that the torque rises because of the valve tolerances the adaptation is to be performed in that the slope of the characteristic curve is corrected downward a greater valve tolerance means for example that the injection opening of the valve is larger than intended whereby more fuel is injected in a variant of the method according to an embodiment the valve stroke is decreased and the activation time is increased so that the torque of the engine also would remain constant here with a reference valve as a.