fuel flow and / or engine speed is electrically controlled in accordance with a rate - of - change value computed from one or more sensed parameters such as accelerator pedal position , throttle position , engine speed , exhaust temperature , intake manifold pressure , fuel temperature , etc . as well as stored engine parameters . a difference between a desired rate - of - change and a measured actual rate - of - change in engine speed is used to correspondingly change an engine control , for example a fuel control rack in a diesel engine fuel pump , a throttle valve in a carburetor , a timer for a fuel injection valve , a fuel valve to a turbine , or other control . the desired rate of change in engine speed may be critically damped , for example by multiplying by a percent or other fraction of a difference between a desired fuel flow and a present fuel flow , so as to avoid overshoot . the control may be operated in min - max , all - speed , cruise control or other special speed control modes , as well as incorporating altitude adjustment , pollution emission control , timing advance control , excessive speed control , fuel control recalibration , counting of selective numbers of pulses from a timing wheel with extension of time for slow speeds , manually selectable low idle adjustment , recordation of operation at excessive engine speed , operating time or other event , fuel consumption economy maximizing , and / or anti - tampering features . in one particular application , the electronic control replaces a governor on a diesel engine and provides maximum power and torque control which may be changed by sensed changed operating conditions such as different transmission gear ranges . a standard computerized control can be employed for different engines with different engine parameters and manufacturing variations compensated by factors stored in rom during final engine testing .