TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred System: In the system for regulating the operation of the engine, the product gas generator comprises: converter for generating a stoichiometric mix of hydrogen and oxygen from water. The product gas generator further comprises: a catalyst mixed into the water to facilitate the electrolysis of the water. The catalyst comprises: at least one ionic salt that stays dissolved in solution in water. The product gas generator comprises: electrolysis system for using an electric current to dissociate a stoichiometric mix of hydrogen atoms and oxygen atoms from water. The product gas generator further comprises: a catalyst mixed into the water to facilitate the electrolysis of the water. The catalyst comprises: at least one ionic salt that stays dissolved in solution in water. The product gas injector comprises: hydrocarbon fuel consumption monitor for determining at least one engine operating characteristic from the set of engine operating characteristics including, but not limited to: hydrocarbon fuel flow from the source of hydrocarbon fuel, diesel engine throttle setting, diesel engine Revolutions Per Minute, diesel engine turbocharger Revolutions Per Minute, internal diagnostic array of the diesel engine, exhaust flow of the combustion by-products, diesel engine cylinder pressure, and the like, to dynamically determine a volume of hydrocarbon fuel presently consumed by the engine. The product gas injector further comprises: combustion characterization system for storing a set of data indicative of hydrocarbon fuel consumed corresponding to measured values of each selected monitored engine operating characteristic; and product gas volume computer for determining the volume of product gas corresponding to the substantially predetermined ratio of hydrocarbon fuel, from the source of hydrocarbon fuel, presently consumed by the engine, as indicated by the set of data corresponding to measured values of a selected monitored engine operating characteristic. Preferred Method: In regulating the operation of the engine, the step of producing comprises: generating a stoichiometric mix of hydrogen and oxygen from water; and adding a catalyst mixed into the water to facilitate the electrolysis of the water; using an electric current to dissociate a stoichiometric mix of hydrogen atoms and oxygen atoms from water; and adding a catalyst mixed into the water to facilitate the electrolysis of the water. Dynamically adding comprises: determining at least one engine operating characteristic from the set of engine operating characteristics including, but not limited to: hydrocarbon fuel flow from the source of hydrocarbon fuel, diesel engine throttle setting, diesel engine Revolutions Per Minute, diesel engine turbocharger Revolutions Per Minute, internal diagnostic array of the diesel engine, exhaust flow of the combustion by-products, diesel engine cylinder pressure, and the like, to dynamically determine a volume of hydrocarbon fuel presently consumed by the engine; storing a set of data indicative of hydrocarbon fuel consumed corresponding to measured values of each selected monitored engine operating characteristic; and determining the volume of product gas corresponding to the substantially predetermined ratio of hydrocarbon fuel, from the source of hydrocarbon fuel, presently consumed by the engine, as indicated by the set of data corresponding to measured values of a selected monitored engine operating characteristic.