on the other printed in electrically conductive ink printed conductors on both sides connect the heating element and ion sensor with an outer end of the glow sensor element for connection with an electric power source an insulating coating protects the heating element and conductors from exposure to combustion gases various flat plate mounting embodiments are disclosed application_number US 16039798 A description the present invention provides novel glow sensors which may be installed in the glow plug openings of diesel engines of the types previously described these glow sensors provide both the prior glow plug function of assisting in the ignition of the fuel during cold starting and operation and the additional ion sensor function of sensing the occurrence and character of the combustion event in the combustion chamber or pre chamber through variations in ionization of combustion gases within the chamber during combustion in accordance with and for purposes that are known in the art the terms 34 inner end 34 and 34 outer end 34 as used in the subsequent description and claims refer to directions in the glow sensor as installed in an engine wherein the glow tip forms an inner end extending within a combustion chamber including a pre chamber and electrical terminals are located at an outer end extending outside the engine cylinder head referring now to fig3 of the drawings numeral 10 generally indicates a first embodiment of glow sensor formed in accordance with the invention glow sensor 10 combines the functions of an ignition glow plug and a combustion chamber ion sensor in a single device having the general appearance of a glow plug and able to be.