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 misfire monitoring method and system employ an indicated mean effective pressure (IMEP) parameter for misfire monitoring of an internal combustion engine of a vehicle. The method and system include determining displacement and torque of the engine. An indicated mean effective pressure (IMEP) parameter is then calculated for the engine. The indicated mean effective pressure (IMEP) parameter is engine torque divided by engine displacement. A misfire monitor monitors the indicated mean effective pressure (IMEP) parameter to detect misfire. The method and system include determining maximum indicated mean effective pressure (IMEP_MAX) parameter for the engine. A normalized indicated mean effective pressure (IMEP_LOAD) parameter for the engine is then calculated. The normalized indicated mean effective pressure (IMEP_LOAD) parameter is the indicated mean effective pressure (IMEP) parameter divided by the maximum indicated mean effective pressure (IMEP_MAX) parameter.

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 a powertrain including an automatic transmission include determining a value representing requested powertrain output, determining a rotational speed representing current operating conditions, generating a command to initiate a ratio change in the automatic transmission, and determining a dynamic pressure for the automatic transmission during the ratio change based on the requested powertrain output and the rotational speed. The requested powertrain output may be a wheel torque determined in part by accelerator pedal position. A performance adder based on requested wheel torque may be provided to further enhance operation.

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 nitrous oxide trap temperature control system for desulfating the trap uses and engine with some cylinders operating with lean combustion and some cylinders operating with rich combustion. The lean and rich combustion gases are combined to form an mixture which is fed to the trap to provide an exothermic reaction. The desired lean and rich air/fuel ratios of the respective lean and rich cylinders are determined based in part on the difference between the trap temperature and a desired trap temperature. The desired lean and rich air/fuel ratios of the respective lean and rich cylinders are also determined from the desired mixture air/fuel ratio entering the trap.

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.

Abstract: An inferred manifold absolute pressure based in part on measured manifold mass air flow is compared with a measured manifold absolute pressure from a MAP sensor and if the rolling average of the difference between the two exceeds either a rich or lean limit, an indicator is energized and a code is stored to identify possible MAP sensor deterioration.

Abstract: A system for calibrating production throttle bodies in which a throttle body (18) is mounted in a fixture (16) and light is transmitted by a light source (12) through the throttle body main bore (20) onto a translucent screen (22). A camera (14) senses the light regions (34) and transmits the information to a controller (26), which calculates the angular position of the throttle valve (32).