A vehicle power steering system suppresses chattering, i.e., unpleasant noises in the form of mechanical and generally higher frequency oscillations resulting from backlash in a gear connection transmitting the torque from the motor to the steering wheel mechanics, produced under certain driving conditions. A control system is provided which evaluates the rotor rpm of the electric motor, and increases the dynamic response time of the rotor in the event that the evaluation of the rotor rpm indicates an unstable state of the control system. As a result, chattering is suppressed only when a critical driving situation arises in which the control system becomes unstable, while, in the normal state, the steering system exhibits all properties thereof, and is neither delayed nor limited in a dynamic behavior thereof.