The present invention relates to a flame glow plug having a combustion chamber which has an outlet opening for the flame, a fuel supply, in particular a blockable fuel supply, for the provision of a fuel flow to the combustion chamber, an air supply for the provision of an air flow to the combustion chamber and an ignition device, in particular an electrically operated heating element, which is arranged in the combustion chamber or which extends into the combustion chamber and which is made to ignite the air/fuel mixture arising from the provided fuel flow and the provided air flow. The air supply is made controllable in quantity to selectively operate the flame glow plug as a torch or as a secondary fuel injection apparatus. The invention furthermore relates to a regeneration apparatus for a particulate filter of an exhaust gas system, to an exhaust gas system for a combustion engine as well as to a method for the operation of a regeneration apparatus.