Control valve member of a fuel injector control valve assembly adapted to be arranged in a control valve chamber wherein it is guided in translation along a valve axis between a closed position forbidding fuel to exit a spill orifice and an open position enabling fuel to exit said spill orifice, the control valve member comprising a magnetic armature to which is fixed a seat member wherein, the armature is adapted to cooperate with an electromagnetic solenoid in order for the seat member to be moved between the closed position wherein it is in sealing abutment against a fixed seating face, and the open position wherein said seat member is lifted away from said fixed seating face, characterized in that the control valve member further comprises a spring member adapted to guide in translation along the valve axis the seat member in the control valve chamber and wherein, the armature is a thick disc-like member axially extending between an upper face and an opposed lower face, the seat member comprising a connecting portion fixed to the armature and, a head portion having a sealing face adapted to abut the fixed seating face in closed position, the head portion being on the side of the lower face of the armature and wherein, the spring member is provided with a plurality of resilient limbs extending from a common core to a distal end adapted to be fixed in the control valve chamber and wherein, said core is centrally holed so that the connecting portion of the seat member can be inserted in said hole prior to be tightened in the armature so that, the spring member is fixedly trapped between the lower face of the armature and the head of the control valve member and wherein, the resilient limbs further comprise a peripheral portion erecting from the distal end of each resilient limb, perpendicularly to the limbs, the peripheral portions surrounding the armature and being adapted to be press fitted against the inner peripheral wall of the valve member chamber. the armature is adapted to cooperate with an electromagnetic solenoid in order for the seat member to be moved between the closed position wherein it is in sealing abutment against a fixed seating face, and the open position wherein said seat member is lifted away from said fixed seating face, characterized in that the control valve member further comprises a spring member adapted to guide in translation along the valve axis the seat member in the control valve chamber and wherein, the armature is a thick disc-like member axially extending between an upper face and an opposed lower face, the seat member comprising a connecting portion fixed to the armature and, a head portion having a sealing face adapted to abut the fixed seating face in closed position, the head portion being on the side of the lower face of the armature and wherein, the spring member is provided with a plurality of resilient limbs extending from a common core to a distal end adapted to be fixed in the control valve chamber and wherein, said core is centrally holed so that the connecting portion of the seat member can be inserted in said hole prior to be tightened in the armature so that, the spring member is fixedly trapped between the lower face of the armature and the head of the control valve member and wherein, the resilient limbs further comprise a peripheral portion erecting from the distal end of each resilient limb, perpendicularly to the limbs, the peripheral portions surrounding the armature and being adapted to be press fitted against the inner peripheral wall of the valve member chamber.