a system and method are provided for controlling an internal combustion engine driving a generator / welder or a stand - alone generator . controlling the engine may include altering the engine speed based upon a detected demand on the generator and / or operating parameters of a welder . for example , the engine speed may be increased based on a detected draw on the generator and / or the operating parameters of the welder . in addition , the engine speed may be automatically decreased to a non - standard idle speed or the engine may be automatically turned off if no demand is detected for a period of time . additionally , the engine speed may be increased if only frequency - insensitive demands are detected on the generator . combinations of these and further methods may be executed . various devices are provided for implementing the above methods .