A method for controlling a powertrain of a vehicle adjusts a minimum allowed airflow based on operating conditions. Specifically, when conditions of engine speed and/or vehicle speed area away from idle conditions, no increasing of the minimum allowed airflow is carried out. However, when conditions of engine speed and/or vehicle speed area approaching idle conditions, the minimum allowed airflow is increased to the required airflow for those idle conditions.

A method of generating a shift schedule and combustion mode schedule to optimize performance characteristics of a lean capable, multiple combustion mode engine associated with a manual transmission with a time-variant after-treatment system is disclosed. The method comprises the steps of generating a lowest cost value for fuel economy and vehicle emissions as a function of an engine operating mode, wherein the engine operating mode is selected from a group consisting of a homogeneous stoichiomet...

A method of continuously estimating barometric pressure values for use in an engine control system. The vehicle includes an manifold absolute pressure (MAP) sensor, ambient air temperature sensor and a throttle position sensor. The method comprises the steps of determining the manifold absolute pressure, ambient air temperature, and throttle position. When the throttle position is at wide-open throttle, the method generates a barometric pressure value (P.sub.a.sup.new) as a function of the manif...

A system is disclosed which includes an insert installed in the fuel filler neck on board a vehicle. The insert ensures that only nozzles dispensing both fuel and reductant are allowed to couple with the filler neck.

A method of generating a shift schedule and combustion mode schedule to optimize performance characteristics of a lean capable, multiple combustion mode engine with a time-variant after-treatment system is disclosed. The method comprises the steps of generating a lowest cost value for fuel economy and vehicle emissions as a function of an engine operating mode, wherein the engine operating mode is selected from a group consisting of a homogeneous stoichiometric mode, a homogeneous lean mode, and...

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 adaptiv...

A throttle position system for an internal combustion engine. Included is a method for filtering a throttle position sensor using a maximum allowable rate of change based on factors such as, for example, physical driver limits or physical electronic actuator limits, for rejecting noise spikes. The filtered signal retains the necessary lead for use in air/fuel ratio control while eliminating problems associated with large noise spikes. Fuel is supplied based on the filtered throttle position and ...

A method of controlling intake manifold pressure during startup of a direct injection engine permits a decrease in instantaneous cylinder pressure by reducing intake manifold pressure thereby increasing the time available for fuel injection during the compression stroke, which allows sufficient fuel to be injected at the lower fuel pressures present during starting of this engine.

A system and method for transient torque control of a direct injection spark ignition engine include controlling airflow and fuel flow rather than ignition timing so that spark timing may be set for best fuel economy. The system and method are particularly suited for variable cam timing or variable valve timing DISI engines where valve timing enables a sufficiently fast engine torque response to achieve transient control. The present invention may be used for torque-based speed control strategie...

A reductant injection control strategy for controlling an amount of nitrogen oxide reducing agent injected upstream of a selective reduction catalyst uses a NOx sensor located downstream of the catalyst. An open loop injection quantity is first determined based on operation conditions. Nitrogen oxide conversion efficiency of the catalyst is controlled by controlling the reductant injection based on after catalyst NOx sensor reading and engine out nitrogen oxide concentration.