Abstract: A computer control system is described that monitors the functionality of an emission control device that is capable of storing NOx and oxygen during lean conditions, and releasing/reducing the stored oxygen and NOx during rich operating conditions. The computer uses a readable storage medium having stored data representing instructions executable by a computer. The instructions utilize a ratio between a lean operating time and a rich operating time to determine whether the catalyst has degraded.

Abstract: A computer control system is described that monitors the functionality of an emission control device that is capable of storing NOx and oxygen during lean conditions, and releasing/reducing the stored oxygen and NOx during rich operating conditions. The computer uses a readable storage medium having stored data representing instructions executable by a computer. The instructions utilize a ratio between a lean operating time and a rich operating time to determine whether the catalyst has degraded.

Abstract: A method for predicting oxygen capacity of an LNT during storage phase of such LNT and the amount of NOx stored in the LNT during purge phase thereof as a function of the time history of an output signal produced by an exhaust gas sensor disposed downstream of the LNT. Oxygen storage capacity of the (LNT) is estimated by integrating output signal over time to determine the amount of oxygen stored in the LNT as function of time.

Abstract: A method for predicting oxygen capacity of an LNT during storage phase of such LNT and the amount of NOx stored in the LNT during purge phase thereof as a function of the time history of an output signal produced by an exhaust gas sensor disposed downstream of the LNT. Oxygen storage capacity of the (LNT) is estimated by integrating output signal over time to determine the amount of oxygen stored in the LNT as function of time. The method includes evaluating the integrated output signal at a time the voltage indicates the exhaust has switched from a condition rich of stoichiometry to a condition lean of stoichiometry. A relative amount of oxygen stored in the LNT is calculated at the switch time. The calculation is a function of the air-fuel ratio of the exhaust and an air-fuel ratio of exhaust leaving the LNT.

Abstract: A system and method for controlling air charge motion in the cylinder of a direct injection spark ignition engine during transitions between different combustion modes is provided. The system includes a cam profile switching device that controls the position of an intake valve for the cylinder. The system further includes an electronic control unit configured to control the cam profile switching device to position the intake valve in a first position in advance of the transition and to move the intake valve to a second position when a predetermined condition for transitioning between the two combustion modes is met.

Abstract: A system and method for controlling air charge motion in the cylinder of a direct injection spark ignition engine during transitions between different combustion modes is provided. The system includes a cam profile switching device that controls the position of an intake valve for the cylinder. The system further includes an electronic control unit configured to control the cam profile switching device to position the intake valve in a first position in advance of the transition and to move the intake valve to a second position when a predetermined condition for transitioning between the two combustion modes is met.

Abstract: A system and method for accessing the ability of an emissions control device to releasably store a quantity of a constituent of exhaust gas generated by lean-burn operation of an internal combustion engine during each of a series of storage-purge cycles. The device stores the quantity of the exhaust gas constituent when the exhaust gas directed through the device is lean of stoichiometry during a storage phase of the cycle. The device releases a previously-stored amount of the exhaust gas constituent when the exhaust gas directed through the device is rich of stoichiometry during a subsequent purge phase of the cycle. The method and system determine, during the purge phase of the cycle, a difference between a predicated time required to purge the device with actual time required to purge the device. The predicted time is computed as a function of a parameter of the device. The parameter varies over time.

Abstract: An ignition and fuel control system 10 of a vehicle 18 is provided including a controller 22. The controller 22 is electrically coupled to an ignition system 14, a fuel system 16, a crankshaft position sensor 32, and a camshaft position sensor 34. The crankshaft position sensor 32 senses a crankshaft position and generates a crankshaft position signal. A camshaft position sensor 34 senses a camshaft position and generates a camshaft position signal. The controller 22 determines a crankshaft position and a camshaft position in response to the crankshaft position signal and the camshaft position signal respectively. The controller 22 identifies a reference engine cylinder in response to the crankshaft position and the camshaft position and generates a synchronization value. The controller 22 also enables the ignition system 14 and the fuel system 16 in response to the synchronization value.