Patent ID: 7654243

Claim:
A method for facilitating vaporization of a fuel in a direct-injection four-stroke internal-combustion engine that can run according to a homogeneous operating mode and to a conventional operating mode, the engine comprising at least one cylinder with a combustion chamber, at least one fluid intake means with an intake pipe and an intake valve, at least one burnt gas exhaust means with an exhaust pipe and an exhaust valve, valve opening/closing control means and fuel injection means, comprising: in the vicinity of the intake phase start, opening the exhaust valve so as to feed again into the combustion chamber at least part of the burnt gas contained in the exhaust pipe, and then, in the vicinity of the intake phase start and after opening the exhaust valve, opening the intake valve so as to allow the intake fluid into the combustion chamber, prior to the end of the intake phase, closing the exhaust valve, in the vicinity of the intake phase end, closing the intake valve, and during the intake phase, carrying out at least one fuel injection into said combustion chamber.