Abstract: An electronic valve actuation system and control method is described. The valve timing is changed between early and late intake valve closing depending on engine operating conditions. Further, valve timing is adjusted to control engine airflow or engine torque. Finally, air-fuel ratio is adjusted based on feedback from an exhaust gas oxygen sensor as well as an estimate of air, fuel, and residual exhausted from cylinders operating with late valve closing (after bottom dead center) timing.

Abstract: Piston to valve interference in an internal combustion engine is detected and alleviated by adjusting valve timing, valve lift, and/or compression ratio. Specifically, based on actuator motion, an actuator is selected to reduce potential interference. Further, potential sensor and hardware degradation are considered in controlling actuators to reduce potential interference.

Abstract: An electronic valve actuation system and control method is described. The valve timing is changed between early and late intake valve closing depending on engine operating conditions. Further, valve timing is adjusted to control engine airflow or engine torque. Finally, air-fuel ratio is adjusted based on feedback from an exhaust gas oxygen sensor as well as an estimate of air, fuel, and residual exhausted from cylinders operating with late valve closing (after bottom dead center) timing.

Abstract: Piston to valve interference in an internal combustion engine is detected and alleviated by adjusting valve timing, valve lift, and/or compression ratio. Specifically, based on actuator motion, an actuator is selected to reduce potential interference. Further, potential sensor and hardware degradation are considered in controlling actuators to reduce potential interference.

Abstract: A method is described for estimating cylinder charge using either the throttle position or mass air flow sensor. The method saves calibration and development expenses by using the same manifold filling model approach regardless of which sensor, or combination of sensors, is used.

Abstract: A system and method for controlling first and second phase shiftable camshafts in a variable cam timing engine is provided. The method includes determining when the first camshaft is moving toward a first scheduled phase angle with respect to the crankshaft with a larger camshaft angular positioning error than the second camshaft. Finally, the method includes slowing down the first camshaft so that synchronized camshaft positioning can be better achieved.

Abstract: An electronic valve actuation system and control method is described. The valve timing is changed between early and late intake valve closing depending on engine operating conditions. Further, valve timing is adjusted to control engine airflow or engine torque. Finally, air-fuel ratio is adjusted based on feedback from an exhaust gas oxygen sensor as well as an estimate of air, fuel, and residual exhausted from cylinders operating with late valve closing (after bottom dead center) timing.

Abstract: A method is described for estimating cylinder charge using either the throttle position or mass air flow sensor. The method saves calibration and development expenses by using the same manifold filling model approach regardless of which sensor, or combination of sensors, is used.

Abstract: A control method adjusts fuel injection into an engine having a variable compression ratio. The method determines the cylinder air amount based on various sensors and the current compression ratio. The disclosed fuel injection method can perform both open loop and closed loop control. A method is also disclosed for putting the compression ratio to a base value during engine shutdown so that subsequent engine starts occur with a consistent compression ratio.

Abstract: A method for estimating operating parameters of an internal combustion engine uses data stored as a function of intake and exhaust valve timing. In particular, the parameters are stored at a default operating point, several stability limited points, a high performance point, and an intermediate point. An inverse distance interpolation algorithm is used to calculated current slope and offset values at the current operating conditions. From these calculated slope and offset values, engine operating parameters, such as manifold pressure and cylinder air amount, are estimated.

Abstract: A system and method for predicting cylinder air charge in an internal combustion engine for a future cylinder event is provided. The pressure in an intake manifold is calculated and an estimated position for a throttle plate of the engine at least one cylinder event in the future is determined responsive to an electronic throttle control command. A rate of change of pressure in the intake manifold is then estimated responsive to the measured intake manifold pressure and the estimated throttle plate position. The cylinder air charge is then calculated responsive to the rate of change in pressure in the intake manifold.

Abstract: A system and method for predicting cylinder air charge in an internal combustion engine for a future cylinder event is provided. The pressure in an intake manifold is calculated and an estimated position for a throttle plate of the engine at least one cylinder event in the future is determined responsive to an electronic throttle control command. A rate of change of pressure in the intake manifold is then estimated responsive to the measured intake manifold pressure and the estimated throttle plate position. The cylinder air charge is then calculated responsive to the rate of change in pressure in the intake manifold.

Abstract: A system (12) and method for determining a value for a control variable for an engine (10) are provided. The system (12) includes an electronic control unit (ECU) (62) configured to obtain a plurality of pairs of programmed timing values for the opening and closing, respectively, of an intake valve (30) and exhaust valve (32) in a cylinder (14) of the engine (10) responsive to different sets of engine operating conditions. The ECU (62) is further configured to obtain a corresponding plurality of conditional values for the control variable responsive to the speed of, and load on, the engine (10) and the plurality of pairs of programmed timing values. Finally, the ECU (62) is configured to determine through interpolation the value for the control variable responsive to the plurality of conditional values. The system and method enable accurate determination of engine control variables during transient conditions using existing engine data.

Abstract: A method for estimating operating parameters of an internal combustion engine uses data stored as a function of intake and exhaust valve timing. In particular, the parameters are stored at a default operating point, several stability limited points, a high performance point, and an intermediate point. An inverse distance interpolation algorithm is used to calculated current slope and offset values at the current operating conditions. From these calculated slope and offset values, engine operating parameters, such as manifold pressure and cylinder air amount, are estimated.

Abstract: A system and method for selecting one of first and second camshafts in an engine is provided. The first and second camshafts control air flow communicating with the first and second cylinders, respectively, of the engine. The engine includes a crankshaft being driven by first and second pistons with the first and second cylinders. The method includes determining which of the first and second camshafts is moving at a faster rate of movement toward a first scheduled phase angle with respect to the crankshaft. Finally, the method includes selecting one of the first and second camshafts having the faster rate of movement for reducing engine torque fluctuations.

Abstract: A system and method for controlling first and second phase shiftable camshafts in a variable cam timing engine is provided. The method includes determining when the first camshaft is moving toward a first scheduled phase angle with respect to the crankshaft at a faster rate than the second camshaft is moving toward the first scheduled phase angle. Finally, the method includes slowing down the first camshaft so that the rate of movement of the first camshaft approaches a rate or movement of the second camshaft toward the first scheduled phase angle.

Abstract: A system and method for controlling first and second phase shiftable camshafts in a variable cam timing engine is provided. The method includes determining when the first camshaft is moving toward a first scheduled phase angle with respect to the crankshaft with a larger camshaft angular positioning error than the second camshaft. Finally, the method includes slowing down the first camshaft so that synchronized camshaft positioning can be better achieved.

Abstract: A control method adjusts fuel injection into an engine having a variable compression ratio. The method determines the cylinder air amount based on various sensors and the current compression ratio. The disclosed fuel injection method can perform both open loop and closed loop control. A method is also disclosed for putting the compression ratio to a base value during engine shutdown so that subsequent engine starts occur with a consistent compression ratio.

Abstract: A method for obtaining an accurate cylinder air-charge estimate is presented. First, a sensor-based powertrain torque estimate is obtained. Next, a torque converter-based powertrain torque estimate is obtained when the torque converter clutch is unlocked. The two estimates are compared, and if they differ by more than a predetermined amount, sensor drift is diagnosed, and corrected.

Abstract: A method of controlling the power output of an internal combustion engine having at least one fuel injector responsive to a commanded fuel signal. The method includes the steps of determining a desired engine power, and determining a first fuel flow value as a function of the desired engine power and engine speed. This first fuel flow value is then compared to the desired fuel flow signal generated by the air-fuel ratio controller. The commanded fuel signal is then limited by the lesser of the desired fuel flow and first fuel flow value. In one aspect of the invention, the desired engine power is calculated by determining a first power value as a function of engine speed and a desired engine torque, and determining a second power value as a function of turbine speed, driveline efficiency and a desired wheel power. The desired engine power is then selected as the lesser of the first and second power values.