Abstract: A system and method for controlling an engine to regulate the oxygen storage level in an emission control device are provided. The system includes oxygen sensors disposed in an exhaust gas stream of the engine upstream and downstream of the emission control device. The oxygen sensors generate a feedgas and tailpipe air fuel signals. The system includes an electronic control unit (ECU) configured to obtain an adjusted feedgas air fuel ratio responsive to the feedgas and tailpipe air fuel signals to correct bias in the feedgas air fuel signal. The (ECU) is further configured to obtain an estimate of an oxygen storage level in the emission control device responsive to the adjusted feedgas air fuel ratio and the tailpipe air fuel signal. Finally, the (ECU) is configured to generate a control signal for the engine responsive to the adjusted feedgas air fuel ratio and the oxygen storage level estimate.

Abstract: System and method for controlling an engine to regulate the oxygen storage level in an emission control device are provided. The system includes oxygen sensors disposed in an exhaust gas stream of the engine upstream and downstream of the emission control device. The oxygen sensors generate a feedgas air fuel signal and a tailpipe air fuel signal. The system further includes an electronic control unit configured to obtain an adjusted feedgas air fuel ratio responsive to the feedgas air fuel signal and the tailpipe air fuel signal in order to correct any bias in the feedgas air fuel signal. The electronic control unit is further configured to obtain an estimate of an oxygen storage level in the emission control device responsive to the adjusted feedgas air fuel ratio and the tailpipe air fuel signal.

Abstract: A method of operating a variable compression, direct injection spark ignited internal combustion engine includes the steps of determining a demanded torque output of the engine, determining a current combustion mode and a current compression ratio mode of the engine; transitioning operation of the engine from the current combustion mode to a new combustion mode to produce the demanded torque output, and transitioning operation of the engine from the current compression ratio mode to a new compression ratio mode so as to minimize torque disturbances during the transitioning of engine operation from the current combustion mode to the new combustion mode.

Abstract: A system and a method for improving engine performance by utilizing a variable compression ratio mechanism and a boosting mechanism are presented. The performance is improved by coordinating the control of ignition timing, compression ratio, and engine boosting while at the same time minimizing engine knock, preventing undesirable interaction, and providing optimal fuel economy. According to the present invention, adjusting ignition timing and compression ratio can be done either sequentially or concurrently.

Abstract: A method of operating a variable compression, direct injection spark ignited internal combustion engine includes the steps of determining a demanded torque output of the engine, determining a current combustion mode and a current compression ratio mode of the engine; transitioning operation of the engine from the current combustion mode to a new combustion mode to produce the demanded torque output, and transitioning operation of the engine from the current compression ratio mode to a new compression ratio mode so as to minimize torque disturbances during the transitioning of engine operation from the current combustion mode to the new combustion mode.

Abstract: A torque control system for a lean burn engine utilizing a supplemental torque apparatus that is operable during the engine mode transition from a lean air/fuel ratio to a rich air/fuel ratio. The supplemental torque apparatus 34, STA, operates to maintain the basic engine torque equation: Te+Tsta=Td such that the device or a electrically connected battery 38 absorbs extra engine torque during a predetermined time period and generates engine torque at times other than the predetermined time period. During the predetermined time period, a Lean NOx Trap 26 in the exhaust system is purged.

Abstract: A control method and system are disclosed for managing torque during a transition in an internal combustion engine. Spark timing and unequal delivery of fuel to engine cylinders both impact torque and are used to provide smooth torque during a transition.

Abstract: A method of modeling and controlling a direct injection stratified charge (DISC) engine coupled to a lean NOx trap that is periodically purged. The method comprises the steps of receiving as inputs a plurality of engine operating parameters and generating an indicated engine torque value, feedgas emission values, and an exhaust gas temperature value. Each of the output values is generated in accordance with a respective hybrid DISC engine model including an engine torque model, a feedgas emissions model, and an exhaust gas temperature model. The feedgas emissions model and exhaust gas temperature models further include submodels for generating output values as a function of either stratified or homogeneous engine operation.

Abstract: A torque control system for a lean burn engine utilizing a supplemental torque apparatus that is operable during the engine mode transition from a lean air/fuel ratio to a rich air/fuel ratio. The supplemental torque apparatus 34, STA, operates to maintain the basic engine torque equation T.sub.e +T.sub.sta =T.sub.d, such that the device or a electrically connected battery 38 absorbs extra engine torque during a predetermined time period and generates engine torque at times other than the predetermined time period. During the predetermined time period, a lean NOx Trap 26 in the exhaust system is purged.

Abstract: A vapor recovery control system for a direct injection spark ignition engine is used to purge vapors in both a homogeneous air/fuel and stratified air/fuel mode. When purging vapors in a stratified mode, a portion of the cylinders receive purge vapors and operate in a homogeneous mode while the rest of the cylinders continue to operate in a stratified mode.

Abstract: An electronic engine controller (EEC) for an internal combustion engine develops an estimate of air charge by receiving a signal from an air meter positioned in an intake manifold of the engine. The signal is indicative of mass flow rate of air past the meter. In one embodiment EEC develops an air charge estimate by developing a first pressure value which is indicative of the pressure in the intake manifold. A pressure correction term is then generated and added to the first pressure value to generate an improved estimate, which takes the dynamic response of the air meter into account, of pressure in the intake manifold. The air charge estimate is then developed from the pressure estimate. In another embodiment, a first mass value, which is indicative of the mass of air in the intake manifold is developed. A mass correction term is then generated and added to the first mass value to generate the improved estimate.