ELECTRONIC CONTROL OF ENGINE FUEL INJECTION BASED ON ENGINE DUTY CYCLE

A control system for controlling fueling and/or timing of a fuel injector in an internal combustion engine. Fuel injection is controlled based upon the recent operating history of the engine. In particular, the difference between the instantaneous speed and the average speed over a previous predetermined period are compared and the difference is utilized in determining a control variable which in turn can be used for selecting fueling and/or timing values. The difference between the instantaneous fueling and the average fueling over a predetermined period can also be used in selecting the control variable. The fuel injector fueling and/or timing is determined utilizing fueling and/or timing values from at least two maps, with the control variable determining the proportions of the timing/fueling valves to be utilized in determining commanded timing/fueling. The control variable may also be set to a fixed value under certain conditions such as during operation on a governor, or where the operator selects an override function.