Abstract: Various methods are described for controlling engine operation for an engine having a turbocharger and direction injection. One example method includes performing at least a first and second injection in response to a driver action. The first and second injection may be performed during a cylinder cycle, the first injection generating a lean combustion and the second injection injected after combustion such that it exits the cylinder unburned into the exhaust upstream of a turbine of the turbocharger.

Abstract: A system and method for controlling an internal combustion engine to improve air/fuel ratio control using a feed-forward observer-based control strategy include estimating current and future airflow actuator positions, determining corresponding mass airflow values, and determining a future in-cylinder air charge based on a difference between the current and future mass airflow values. In one embodiment, the difference between current and future mass airflow estimates is used as a feed-forward term and combined with a sensed or measured value generated by a mass airflow sensor prior to being processed using a manifold filling model to predict the future cylinder air charge.

Abstract: A system and method wherein a torque monitoring algorithm compares torque demand (i.e., driver-demanded torque computed primarily from acceleration pedal position), with two independent torque estimates (e.g., one estimated from throttle position and one estimated from mass airflow (MAF) to the intake manifold). If the maximum of the two actual torque estimates exceeds the driver-demanded torque, the monitoring algorithm logic intervenes in engine torque production (e.g., shuts off fuel to cylinders) and lights a service (wrench) light. In order to prevent, or minimize, unnecessary engine torque production intervention, reducing a torque demand signal to the throttle by a factor, such factor being a function of airflow meter load divided by throttle load. If the air-meter reads higher than the throttle based estimate of air and torque, then the method simply closes the throttle until the air-meter is satisfied.

Abstract: A system and method wherein a torque monitoring algorithm compares torque demand (i.e., driver-demanded torque computed primarily from acceleration pedal position), with two independent torque estimates (e.g., one estimated from throttle position and one estimated from mass airflow (MAF) to the intake manifold). If the maximum of the two actual torque estimates exceeds the driver-demanded torque, the monitoring algorithm logic intervenes in engine torque production (e.g., shuts off fuel to cylinders) and lights a service (wrench) light. In order to prevent, or minimize, unnecessary engine torque production intervention, reducing a torque demand signal to the throttle by a factor, such factor being a function of airflow meter load divided by throttle load.

Abstract: A control system (10) and method for controlling an operational position of a throttle valve in an engine. The system includes a position sensor (16) operably connected to the throttle valve that generates a first signal. A controller is operably connected to the position sensor. The controller (18) is configured to determine a current position of the throttle valve using a transfer function defining a curve with no breakpoints and the signal from the position sensor. The controller (18) is further configured to change the operational position of the throttle valve based on the current position and a desired position of the throttle valve.

Abstract: A system and method for controlling an internal combustion engine to improve air/fuel ratio control using a feed-forward observer-based control strategy include estimating current and future airflow actuator positions, determining corresponding mass airflow values, and determining a future in-cylinder air charge based on a difference between the current and future mass airflow values. In one embodiment, the difference between current and future mass airflow estimates is used as a feed-forward term and combined with a sensed or measured value generated by a mass airflow sensor prior to being processed using a manifold filling model to predict the future cylinder air charge.

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.

Abstract: A control system (10) and method for controlling an operational position of a throttle valve in an engine. The system includes a position sensor (16) operably connected to the throttle valve that generates a first signal. A controller is operably connected to the position sensor. The controller (18) is configured to determine a current position of the throttle valve using a transfer function defining a curve with no breakpoints and the signal from the position sensor. The controller (18) is further configured to change the operational position of the throttle valve based on the current position and a desired position of the throttle valve.

Abstract: A system and method for controlling an internal combustion engine to improve air/fuel ratio control using a feed-forward observer-based control strategy include estimating current and future airflow actuator positions, determining corresponding mass airflow values, and determining a future in-cylinder air charge based on a difference between the current and future mass airflow values. In one embodiment, the difference between current and future mass airflow estimates is used as a feed-forward term and combined with a sensed or measured value generated by a mass airflow sensor prior to being processed using a manifold filling model to predict the future cylinder air charge.

Abstract: A system and method for controlling an internal combustion engine to improve air/fuel ratio control using a feed-forward observer-based control strategy include estimating current and future airflow actuator positions, determining corresponding mass airflow values, and determining a future in-cylinder air charge based on a difference between the current and future mass airflow values. In one embodiment, the difference between current and future mass airflow estimates is used as a feed-forward term and combined with a sensed or measured value generated by a mass airflow sensor prior to-being processed using a manifold filling model to predict the future cylinder air charge.

Abstract: A system and method for controlling an internal combustion engine to improve air/fuel ratio control using a feed-forward observer-based control strategy include estimating current and future airflow actuator positions, determining corresponding mass airflow values, and determining a future in-cylinder air charge based on a difference between the current and future mass airflow values. In one embodiment, the difference between current and future mass airflow estimates is used as a feed-forward term and combined with a sensed or measured value generated by a mass airflow sensor prior to being processed using a manifold filling model to predict the future cylinder air charge.

Abstract: A system and method for controlling a powertrain including an automatic transmission include determining a desired wheel torque, determining engine speed, determining turbine speed, determining a selected gear and associated selected gear ratio, determining a transmission spin loss based on a first function of the turbine speed and the selected gear, determining a transmission torque proportional loss based on a second function of the turbine speed and the selected gear, determining a desired engine torque based on the transmission spin loss, the transmission torque proportional loss, and the selected gear ratio, and controlling the powertrain using the desired engine torque such that actual wheel torque approaches the desired wheel torque. A transmission pump loss may also be determined based on line pressure and engine speed.

Abstract: A system and method for determining control parameters for an engine include modifying a first engine torque based on estimated losses associated with a previously determined desired engine load to determine a second engine torque, modifying the second engine torque based on a desired ignition angle and air/fuel ratio to determine a third engine torque, determining a desired engine load based on the third engine torque, and converting the desired engine load to at least one engine control parameter. The invention recognizes that the transformation between torque and airflow is an affine transformation rather than a linear transformation. The present invention also recognizes the significant interrelations between various engine control parameters such as air/fuel ratio and ignition timing by determining control parameters after the desired torque has been fully compensated for losses and using a single function to account for air/fuel ratio and ignition angle excursions.

Abstract: A computer readable storage medium having instructions for controlling an engine includes instructions for determining a desired engine brake torque and modifying the desired engine brake torque based on current engine operating conditions to determine a requested engine brake torque prior to determination of control parameters, including at least one of an airflow and a fuel quantity, to effect the requested engine brake torque. Preferably, the desired engine brake torque is modified by combining the desired engine brake torque with an idle speed torque to generate a first intermediate torque, comparing the first intermediate torque to an actual engine brake torque to generate a second intermediate torque, generating a feedback correction torque based on the second intermediate torque, and combining the first intermediate torque, the feedback correction torque, and a third intermediate torque to determine the requested engine brake torque.

Abstract: A system and method for controlling an internal combustion engine to improve air/fuel ratio control particularly during transient operating modes include estimating cylinder air charge during a future fuel injection event. The system and method use a dynamic airflow actuator position model to determine future actuator position which is then used by an airflow model and manifold filling model to provide the estimated future cylinder air charge. The system and method use observer-based and adaptive control to compensate for modeling errors and sensor dynamics while assuring stability and accurate prediction of airflow actuator position and airflow.

Abstract: A computer readable storage medium having instructions for controlling an engine includes instructions for determining a desired engine brake torque and modifying the desired engine brake torque based on current engine operating conditions to determine a requested engine brake torque prior to determination of control parameters, including at least one of an airflow and a fuel quantity, to effect the requested engine brake torque. Preferably, the desired engine brake torque is modified by combining the desired engine brake torque with an idle speed torque to generate a first intermediate torque, comparing the first intermediate torque to an actual engine brake torque to generate a second intermediate torque, generating a feedback correction torque based on the second intermediate torque, and combining the first intermediate torque, the feedback correction torque, and a third intermediate torque to determine the requested engine brake torque.

Abstract: A system and method for controlling an engine include determining a desired engine brake torque and modifying the desired engine brake torque based on current engine operating conditions to determine a requested engine brake torque prior to determination of control parameters, including at least one of an airflow and a fuel quantity, to effect the requested engine brake torque. Preferably, the desired engine brake torque is modified by combining the desired engine brake torque with an idle speed torque to generate a first intermediate torque, comparing the first intermediate torque to an actual engine brake torque to generate a second intermediate torque, generating a feedback correction torque based on the second intermediate torque, and combining the first intermediate torque, the feedback correction torque, and a third intermediate torque to determine the requested engine brake torque, where the third intermediate torque represents accessory load or a frictional torque loss which varies with temperature.

Abstract: A system and method for controlling a powertrain including an internal combustion engine include generating a signal indicative of driver requested engine output, generating a signal indicative of current vehicle speed, determining a reference engine output parameter based on the driver requested engine output signal and the signal indicative of current vehicle speed, determining a value indicative of current barometric pressure, modifying the reference engine output parameter based on the value indicative of current barometric pressure, and controlling the engine based on the modified reference parameter. In one embodiment, the invention adjusts a base driver demanded torque based on barometric pressure to preserve full pedal travel and prevent “dead pedal” feel when operating the vehicle at high altitudes and maximum engine torque output.

Abstract: A system and method for controlling a vehicular powertrain including an internal combustion engine, an automatic transmission having a plurality of selectable gear ratios, and a controller in communication with the internal combustion engine, the transmission, and an accelerator pedal, include determining a driver requested wheel torque based on position of the accelerator pedal, and determining a vehicle speed ratio changing threshold based on the driver requested wheel torque. In one embodiment, the system and method determine a value indicative of current barometric pressure, determine a current gear ratio, and modify the driver requested wheel torque based on the current barometric pressure and the current gear ratio to determine a compensated wheel torque. The compensated wheel torque is used to determining the ratio changing threshold. Offset values are included to adjust for barometric pressure variation, transmission oil temperature, and to prevent gear hunting or excessive ratio changing.

Abstract: A system and method for controlling an internal combustion engine using a controller to implement at least two control modes having corresponding first and second mode controllers with disparate control parameters include comparing output of the first and second mode controllers to generate an error, generating a correction value based on the error, and providing the correction value to one of the mode controllers to provide a smooth transition of control between the mode controllers. In one embodiment, the first controller is a torque controller which determines a desired air flow to achieve a desired torque and the second mode controller is an idle speed controller which determines a desired air flow to maintain a desired engine speed. The invention is advantageous in that it provides for smooth transitions between control modes, such as between idle mode and a normal driving mode, by harmonizing the outputs of the controllers.