METHOD FOR CONTROLLING A MOTOR VEHICLE PROVIDED WITH AN INTERNAL COMBUSTION ENGINE HAVING A SYSTEM FOR VARIABLE ACTUATION OF THE INTAKE VALVES

摘要

In a motor vehicle provided with an internal combustion engine having a system for variable actuation of the intake valves there is provided for a phase of activation of an operating mode with the engine off and the vehicle moving, in which the fuel supply to the engine is cut-off. After the cut-off of the fuel supply to the engine, the system for variable actuation of the intake valves is controlled to vary the opening time and/or closing time and/or the lift of the intake valves so as to control the losses due to the pumping effect which occur within the engine in cut-off condition. If the engine is equipped with a starter capable of starting while engine moving, pumping losses are minimised to increase engine run down time. If the engine is equipped with a starter capable of starting only engine at still stand, pumping losses are minimised as long as rpm is above threshold to allow restart by fuel supply and pumping losses are maximised when rpm is below threshold to reach quick stand still for restart by electric starter. This insures quick restart in case of driver change of mind in any case.