Engine testing systems
R.K. Feller, S.R. Warner, J.D. Capriotti · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 1989
This patent describes a method for controlling engine operation during end of production line engine testing. It comprises: determining the air charge of the engine by sensing engine speed and by sensing the throttle angle of the engine; determining a desired engine operating parameter as a function of engine speed and air charge of the engine; operating the engine as a function of the determined desired engine operating parameter; determining if the engine coolant temperature is greater than a predetermined value; establishing the engine is operating at idle state by determining if the engine is operating at a steady state and determining if the throttle angle of the engine is stable, at closed throttle, and if the engine speed is stable; and initiating self test of the engine by; determining if engine coolant temperature is within a predetermined temperature range; determining if engine coolant temperature is above a predetermined temperature magnitude; determining if throttle angle magnitude is within a predetermined range; determining if engine idle speed is greater than a predetermined magnitude; and determining if the duty cycle of a signal applied to an engine idle speed control valve is above a predetermined value.