METHOD TO ADJUST AN INTERNAL COMBUSTION ENGINE AND INTERNAL COMBUSTION ENGINE

A method to adjust an internal combustion engine is described, comprising the steps of: i) controlling a first and second adjustment member so as to adjust a first and second quantity of air in a first and second cylinder provided with a first and second piston; ii) operating a first and second ignition member with a first and second advance angle relative to the first and second top dead centre of the first and second piston; iii) processing a value of one of the amplitudes associated with a respective frequency of a driving member; iv) detecting that the amplitude at a corresponding desired frequency exceeds a threshold value; v) reducing the first advance angle; and vi) increasing the first quantity of air so as to maintain the average value of the resulting torque constant at two complete rotations of said driving member.