A method of operating a compression ignition engine comprises introducing enriching
component to a combustion chamber of the compression ignition engine, wherein the
enriching component comprises hydrogen, carbon monoxide, or a combination comprising
at least one of the foregoing; introducing bulk fuel to the combustion chamber;
heating a glow plug to cause the enriching component to release thermal energy;
and initiating combustion of the bulk fuel with the released thermal energy from
the enriching component.