Abstract: The glow plug comprises a main body (10) inside which there is attached a heating unit (13), a vaporizing chamber (18) and a mixing chamber (32) for mixing flowing air (A) with vaporized fuel supplied via a conduit (19) through a filter (20) and a calibrated conduit (21). A socket (30) is attached to the end of the main body (10), said socket being traversed by a transverse pipe (31) preferably in the shape of a Venturi tube with the narrowed central portion forming the mixing chamber (32) and being located at the level of an end portion of the heating unit (13).