One proposed technique applied to a motor vehicle feedback controls the intake air flow of an internal combustion engine for output of a driving power to set the idling state in a drivable gearshift position and to attain a target creep vehicle speed under the condition of both an accelerator-off position and a brake-off position (see, for example, Japanese Patent Laid-Open Gazette No. H10-166897). This prior art motor vehicle is supposed not to slide down along a slope under the brake-off condition on a hill start.