Patent ID: 6840237

Claim:
An internal combustion engine provided with at least one cylinder and comprising: a fuel injector, through which fuel is injected into a combustion chamber, for each cylinder; a piston in the engine cylinder whose compression action causes a mixture of air and fuel within the combustion chamber to be ignited; at least one inlet valve for admitting gas which includes fresh air into said cylinder; at least one exhaust valve for exhausting combusted gases; a pressure sensor for measuring intake manifold pressure and generating a pressure signal; a sensor for generating a signal representing an actual λ-value; sensors for measuring at least one further engine operation parameter, and a control unit that controls fuel injection quantity per combustion cycle injected through each fuel injector, and during compression ignition mode, the control unit is arranged to select a λ-value from a map stored in the control unit, which value is a function of engine load and engine speed, and to compare the actual λ-value with the selected λ-value; whereby the control unit is arranged to adjust the intake manifold pressure as a function of the difference between the said λ-values in order to obtain the selected λ-value.