Abstract: An idle speed compensation system for a vehicle includes an idle speed control system that varies airflow to an engine at idle and a transmission driven by the engine. A controller communicates with the idle speed control system, the engine, and the transmission. The controller generates an idle speed compensation signal based on a transmission load.

Abstract: A control system and method maintains a constant engine idle speed during a garage shift of an automatic transmission-equipped vehicle with a torque converter. An engine control module or other processor identifies when transmission input clutch fill occurs. The engine control module increases engine output based on the transmission input clutch fill and before a decrease in engine idle speed occurs. The engine control module latches a turbine speed and a speed ratio (turbine speed/engine speed). The engine control module declares transmission input clutch fill if the latched turbine speed minus a current turbine speed is greater than the first calibration constant or if the latched speed ratio minus a current speed ratio is greater than the second calibration constant. The engine control module increases the engine output after waiting a first time delay after the transmission clutch fill.

Abstract: A method is directed to controlling idle speed for an internal combustion engine. The method provides for monitoring a plurality of vehicle system signal inputs, determining a baseline load control signal based on the vehicle system signal inputs, determining a maximum load control signal based on the vehicle system signal inputs, determining an anticipated load control signal based on the vehicle system signal inputs, determining an idle speed control signal based on the baseline control signal and the anticipated control signal, modifying the idle speed control signal based on vehicle system signal inputs, and controlling the idle speed based on the modified idle speed control signal.

Abstract: A method is directed to controlling idle speed for an internal combustion engine. The method provides for monitoring a plurality of vehicle system signal inputs, determining a baseline load control signal based on the vehicle system signal inputs, determining a maximum load control signal based on the vehicle system signal inputs, determining an anticipated load control signal based on the vehicle system signal inputs, determining an idle speed control signal based on the baseline control signal and the anticipated control signal, modifying the idle speed control signal based on vehicle system signal inputs, and controlling the idle speed based on the modified idle speed control signal.

Abstract: A control system and method maintains a constant engine idle speed during a garage shift of an automatic transmission-equipped vehicle with a torque converter. An engine control module or other processor identifies when transmission input clutch fill occurs. The engine control module increases engine output based on the transmission input clutch fill and before a decrease in engine idle speed occurs. The engine control module latches a turbine speed and a speed ratio (turbine speed/engine speed). The engine control module declares transmission input clutch fill if the latched turbine speed minus a current turbine speed is greater than the first calibration constant or if the latched speed ratio minus a current speed ratio is greater than the second calibration constant. The engine control module increases the engine output after waiting a first time delay after the transmission clutch fill.

Abstract: A motor vehicle has a multi-speed automatic transmission and a cruise control system. A method of shift control when the cruise control system is enabled infers from a plurality of factors based on cruise control error quantities the desirability of forcing a downshift to a lower speed ratio.