An electrically operated bistable fluid valve for controlling a fluid flow in a fluid passage in a fuel supply unit, e.g. a carburettor or a low pressure injection system, of an internal combustion engine, the fluid valve (40; 60) including: - an axially moveable plunger (41; 61) including a permanent magnet (42; 62) having its magnetic direction axially oriented providing a front pole (42a; 62a) and a rear pole (42b; 62b); - an axially extending chamber (43; 63) with two opposite located valve seats (44, 45; 64, 65) limiting the axial movement of the plunger (41; 61), a front valve seat (44; 64) facing the front pole (42a; 62a) and a rear valve seat (45; 65) facing the rear pole (42b; 62b); - at least one front ferromagnetic element (46; 66) and a rear ferromagnetic element (47; 67), enabling two stable valve positions, a closed position, when the plunger (41; 61) rests at the front valve seat (44; 64), preventing fluid flow in the fluid passage, and an open position, when the plunger (41; 61) rests at the rear valve seat (45; 65), allowing fluid flow in the fluid passage, by designing the forces between the magnet (42; 62) and respectively ferromagnetic element (46, 47; 66, 67) so that the magnetic force between the front pole (42a; 62a) and the front ferromagnetic element (46; 66) is stronger than the magnetic force between the rear pole (42b; 62b) and the rear ferromagnetic element (47; 67) when the plunger (41; 61) is at the front valve seat (44; 64) and so that the magnetic force between the rear pole (42b; 62b) and the rear ferromagnetic element (47; 67) is stronger than the magnetic force between the front pole (42a; 62a) and the front ferromagnetic element (46; 66) when the plunger (41; 61) is at the rear valve seat (45; 65); and - electromagnetically operating means (48a, 48b; 68a, 68b) to axially snap the plunger (41; 61) between the two stable valve positions when energized, and when not energized the plunger (41; 61) is held in either of the two stable positions enabled by the ferromagnetic elements (46, 47; 66, 67); wherein at the closed respectively open position the magnet (42; 62) of the plunger (41; 61) and the corresponding ferromagnetic element (46, 47; 66, 67) are distanced from direct contact with each other, and the at least one front ferromagnetic element (46; 66) is located at the front valve seat (44; 64) and the rear ferromagnetic element (47; 67) is located at the rear valve seat (45; 65), wherein the front valve seat is provided with an opening (51; 71), characterized in that the front valve seat (44; 64) or the contacting portion of the plunger (41; 61) for abutting the front valve seat (44; 64) is of non-magnetic material to avoid direct contact between the front ferromagnetic element (46; 66) and the magnet (42; 62) of the plunger (41; 61). - an axially moveable plunger (41; 61) including a permanent magnet (42; 62) having its magnetic direction axially oriented providing a front pole (42a; 62a) and a rear pole (42b; 62b); - an axially extending chamber (43; 63) with two opposite located valve seats (44, 45; 64, 65) limiting the axial movement of the plunger (41; 61), a front valve seat (44; 64) facing the front pole (42a; 62a) and a rear valve seat (45; 65) facing the rear pole (42b; 62b); - at least one front ferromagnetic element (46; 66) and a rear ferromagnetic element (47; 67), enabling two stable valve positions, a closed position, when the plunger (41; 61) rests at the front valve seat (44; 64), preventing fluid flow in the fluid passage, and an open position, when the plunger (41; 61) rests at the rear valve seat (45; 65), allowing fluid flow in the fluid passage, by designing the forces between the magnet (42; 62) and respectively ferromagnetic element (46, 47; 66, 67) so that the magnetic force between the front pole (42a; 62a) and the front ferromagnetic element (46; 66) is stronger than the magnetic force between the rear pole (42b; 62b) and the rear ferromagnetic element (47; 67) when the plunger (41; 61) is at the front valve seat (44; 64) and so that the magnetic force between the rear pole (42b; 62b) and the rear ferromagnetic element (47; 67) is stronger than the magnetic force between the front pole (42a; 62a) and the front ferromagnetic element (46; 66) when the plunger (41; 61) is at the rear valve seat (45; 65); and - electromagnetically operating means (48a, 48b; 68a, 68b) to axially snap the plunger (41; 61) between the two stable valve positions when energized, and when not energized the plunger (41; 61) is held in either of the two stable positions enabled by the ferromagnetic elements (46, 47; 66, 67); wherein at the closed respectively open position the magnet (42; 62) of the plunger (41; 61) and the corresponding ferromagnetic element (46, 47; 66, 67) are distanced from direct contact with each other, and the at least one front ferromagnetic element (46; 66) is located at the front valve seat (44; 64) and the rear ferromagnetic element (47; 67) is located at the rear valve seat (45; 65), wherein the front valve seat is provided with an opening (51; 71), characterized in that the front valve seat (44; 64) or the contacting portion of the plunger (41; 61) for abutting the front valve seat (44; 64) is of non-magnetic material to avoid direct contact between the front ferromagnetic element (46; 66) and the magnet (42; 62) of the plunger (41; 61).