In a method for adjusting an operating variable of an internal combustion engine in a motor vehicle, an electric generator is driven by the internal combustion engine and a current output value of a mechanical driving power required by the generator is repeatedly determined from at least one current parameter value of the generator by an energy management unit. On the basis of the output value, an engine control unit determines a control setpoint for adjusting the operating variable. Sudden load variations at the generator are compensated by monitoring an operating variable of the generator, by determining after a sudden load variation of the electrical load a relative change of the operating variable and by determining an adjusted control setpoint caused by the sudden load variation independently of the output value of the energy management unit and dependent on the relative change in the monitored operating variable.