Abstract: A slider control module, based on a mode command: selectively extends pins into one or more slider actuators of a camshaft slider. Contact between the pins and the grooves in the slider actuator(s) during rotation of a camshaft slides the camshaft slider axially along the intake camshaft. An actual mode module: determines a last stored indicator of the mode command; commands the slider control module to extend one of the pins to slide the camshaft slider and achieve the last stored indicator of the mode command; and, based on whether the one of the pins extended in response to the command, indicates that an actual mode is either: (i) the last stored indicator of the mode command; or (ii) another mode. The mode command module updates the mode command to the actual mode.

Abstract: An engine control module includes at least one high side driver connected to at least one intake camshaft actuator and at least one exhaust camshaft actuator. A plurality of low side drivers is connected to the at least one intake camshaft actuator and the at least one exhaust camshaft actuator. A sliding camshaft control module selectively actuates the at least one high side driver and the plurality of low side drivers based on a status associated with the at least one intake camshaft actuator and/or the at least one exhaust camshaft actuator.

Abstract: A control system for a recirculation valve of a turbocharger includes a target boost module, a close request module, and a close delay module. The target boost module determines a target boost for the turbocharger based on a torque request. The close request module selectively generates a close request to close the recirculation valve based on the target boost. The close delay module, in response to the generation of the close request, delays closing of the recirculation valve.

Abstract: A system according to the principles of the present disclosure includes a switching period module and at least one of a valve lift control module and a start-stop control module. The switching period module determines a switching period that elapses as a valve lift actuator of an engine switches between a first valve lift position and a second valve lift position that is different than the first lift position. The switching period begins when a measured position of the valve lift actuator corresponds to the first lift position and the switching period ends when the measured position of the valve lift actuator corresponds to the second lift position. The valve lift control module controls the valve lift actuator based on the switching period. The start-stop control module determines whether to automatically stop the engine based on the switching period.

Abstract: An engine control system for a vehicle includes a target torque module that determines a target torque output of an engine based on at least one driver input. A target air per cylinder (APC) module determines a target APC for the engine based on the target torque. A target mass airflow (MAF) module determines a target MAF through a throttle valve of the engine based on the target APC, a number of activated cylinders of the engine, and a total number of cylinders of the engine. A throttle control module determines a target throttle opening based on the target MAF and controls opening of the throttle valve based on the target throttle opening.

Abstract: An exhaust system for a lean-burn internal combustion engine is described, and includes an injection system for injecting reductant into an exhaust gas feedstream upstream of a selective catalytic reduction device (SCR). A control method for controlling the injection system includes determining an upstream NOx gas concentration upstream of the SCR device, determining a measured downstream NOx gas concentration based upon a signal output from a sensor configured to monitor NOx gas concentration downstream of the SCR device, and determining an estimated downstream NOx gas concentration based upon an executable model. A first correlation between the upstream NOx gas concentration and the measured downstream NOx gas concentration is determined, and a second correlation between the upstream NOx gas concentration and the estimated downstream NOx gas concentration is determined. The reductant injection is controlled based upon the first and second correlations.

Abstract: An exhaust system for a lean-burn internal combustion engine is described, and includes an injection system for injecting reductant into an exhaust gas feedstream upstream of a selective catalytic reduction device (SCR). A control method for controlling the injection system includes determining an upstream NOx gas concentration upstream of the SCR device, determining a measured downstream NOx gas concentration based upon a signal output from a sensor configured to monitor NOx gas concentration downstream of the SCR device, and determining an estimated downstream NOx gas concentration based upon an executable model. A first correlation between the upstream NOx gas concentration and the measured downstream NOx gas concentration is determined, and a second correlation between the upstream NOx gas concentration and the estimated downstream NOx gas concentration is determined. The reductant injection is controlled based upon the first and second correlations.

Abstract: A slider control module, based on a mode command: selectively extends pins into one or more slider actuators of a camshaft slider. Contact between the pins and the grooves in the slider actuator(s) during rotation of a camshaft slides the camshaft slider axially along the intake camshaft. An actual mode module: determines a last stored indicator of the mode command; commands the slider control module to extend one of the pins to slide the camshaft slider and achieve the last stored indicator of the mode command; and, based on whether the one of the pins extended in response to the command, indicates that an actual mode is either: (i) the last stored indicator of the mode command; or (ii) another mode. The mode command module updates the mode command to the actual mode.

Abstract: A system includes a filtering module that filters a first signal that indicates an amount of nitrogen oxides (NOx) in exhaust gas upstream from a catalyst, and that filters a second signal that indicates amounts of NOx and ammonia (NH3) in exhaust gas downstream from the catalyst. A slip determination module determines whether NH3 is present in exhaust gas downstream from the catalyst based on a frequency response of the first and second signals.

Abstract: A method of controlling an engine includes initiating a transition from homogenous charge compression ignition (HCCI) to spark ignited (SI) combustion mode of the engine under low load. The method includes commanding an exhaust valve actuator to increase lift of the exhaust valve to maximize expulsion of combustion chamber contents. The method also includes injecting into the combustion chamber sufficient amount of fuel after the lift of the exhaust valve was increased to generate substantially stoichiometric air-fuel ratio of the gas mixture contained in the chamber. The method also includes igniting the gas mixture after the fuel was injected into the combustion chamber to maximize combustion of the gas mixture. The method additionally includes commanding an intake camshaft phaser to change the position of the intake camshaft to a position configured for predetermined throttled SI combustion mode after the gas mixture was ignited to maximize operating efficiency of the engine.

Abstract: A method for controlling a turbocharger is provided. The turbocharger has a turbine operatively connected to an exhaust of an internal combustion engine, and a compressor operatively connected to an intake of the engine. The method includes determining a boost pressure command for the compressor. The boost pressure command is configured to provide sufficient combustion reactant for the engine. The method includes calculating a compressor power from the determined boost pressure command, and calculating a turbine flow from the calculated compressor power. The method commands the turbocharger to operate at the calculated turbine flow.

Abstract: An engine control system for a vehicle includes a target torque module that determines a target torque output of an engine based on at least one driver input. A target air per cylinder (APC) module determines a target APC for the engine based on the target torque. A target mass airflow (MAF) module determines a target MAF through a throttle valve of the engine based on the target APC, a number of activated cylinders of the engine, and a total number of cylinders of the engine. A throttle control module determines a target throttle opening based on the target MAF and controls opening of the throttle valve based on the target throttle opening.

Abstract: A method is disclosed for controlling a two-stage turbocharger system having low-pressure and high-pressure turbochargers in line, sequentially, with an engine. The turbochargers include a low-pressure (LP) turbine and an LP compressor, and a high-pressure (HP) turbine and an HP compressor. The LP compressor feeds the HP compressor, which feeds the engine intake. The engine exhaust feeds the HP turbine, which feeds the LP turbine. The method determines a total boost pressure, which provides combustion reactant for the engine. The method calculates an LP compressor power from the determined total boost pressure, and an LP turbine flow from the LP compressor power. The low-pressure turbocharger operates at the calculated LP turbine flow. The method calculates an HP compressor power from the determined total boost pressure, and an HP turbine flow from the HP compressor power. The high-pressure turbocharger operates at the calculated HP turbine flow.

Abstract: A system includes an injector control module and an SCR optimization module. The injector control module controls an amount of ammonia (NH3) stored in a selective catalytic reduction (SCR) catalyst to maintain a first storage level. The SCR optimization module determines whether the first storage level maximizes a conversion efficiency of the SCR catalyst at a first temperature and minimizes a probability of NH3 slip when the temperature of the SCR catalyst transitions from the first temperature to a second temperature. The injector control module controls the amount of NH3 stored in the SCR catalyst to maintain a second storage level when the second storage level maximizes the efficiency of the SCR catalyst relative to the first storage level and minimizes the probability of NH3 slip relative to the first storage level.

Abstract: A method is disclosed for controlling a two-stage turbocharger system having low-pressure and high-pressure turbochargers in line, sequentially, with an engine. The turbochargers include a low-pressure (LP) turbine and an LP compressor, and a high-pressure (HP) turbine and an HP compressor. The LP compressor feeds the HP compressor, which feeds the engine intake. The engine exhaust feeds the HP turbine, which feeds the LP turbine. The method determines a total boost pressure, which provides combustion reactant for the engine. The method calculates an LP compressor power from the determined total boost pressure, and an LP turbine flow from the LP compressor power. The low-pressure turbocharger operates at the calculated LP turbine flow. The method calculates an HP compressor power from the determined total boost pressure, and an HP turbine flow from the HP compressor power. The high-pressure turbocharger operates at the calculated HP turbine flow.

Abstract: An exhaust system is provided. The exhaust system includes a first sensor that senses a level of nitrous oxide (NOx) in exhaust gas and generates a first sensor signal. A second sensor senses a level of ammonia (NH3) in the exhaust gas and generates a second sensor signal. A control module receives the first sensor signal and the second sensor signal, determines a desired reductant dosage based on the first sensor signal and the second sensor signal, and generates an injector control signal based on the desired reductant dosage.

Abstract: A method of controlling an engine includes initiating a transition from homogenous charge compression ignition (HCCI) to spark ignited (SI) combustion mode of the engine under low load. The method includes commanding an exhaust valve actuator to increase lift of the exhaust valve to maximize expulsion of combustion chamber contents. The method also includes injecting into the combustion chamber sufficient amount of fuel after the lift of the exhaust valve was increased to generate substantially stoichiometric air-fuel ratio of the gas mixture contained in the chamber. The method also includes igniting the gas mixture after the fuel was injected into the combustion chamber to maximize combustion of the gas mixture. The method additionally includes commanding an intake camshaft phaser to change the position of the intake camshaft to a position configured for predetermined throttled SI combustion mode after the gas mixture was ignited to maximize operating efficiency of the engine.

Abstract: A method for controlling a turbocharger is provided. The turbocharger has a turbine operatively connected to an exhaust of an internal combustion engine, and a compressor operatively connected to an intake of the engine. The method includes determining a boost pressure command for the compressor. The boost pressure command is configured to provide sufficient combustion reactant for the engine. The method includes calculating a compressor power from the determined boost pressure command, and calculating a turbine flow from the calculated compressor power. The method commands the turbocharger to operate at the calculated turbine flow.

Abstract: A turbocharger control method includes: determining a first desired pressure ratio across a first compressor of a first turbocharger; based on the first desired pressure ratio, determining a first desired duty cycle for a first wastegate of the first turbocharger; determining a second desired pressure ratio across a second compressor of a second turbocharger based on the first desired pressure ratio; based on the second desired pressure ratio, determining a second desired duty cycle for a second wastegate of the second turbocharger; generating a first target duty cycle for the first wastegate based on the first desired duty cycle; opening the first wastegate based on the first target duty cycle; generating a second target duty cycle for the second wastegate based on the second desired duty cycle; and opening the second wastegate based on the second target duty cycle.

Abstract: An exhaust gas treatment system for an internal combustion engine is provided, having an exhaust gas conduit, a reductant source, a temperature sensor, an intake mass air flow sensor, and a control module. The exhaust gas conduit is in fluid communication with, and is configured to receive an exhaust gas from the internal combustion engine. The exhaust gas contains oxides of nitrogen (“NOx”). The reductant source is in fluid communication with the exhaust gas conduit and is configured for injecting an amount of reductant that is released into the exhaust gas conduit. The temperature sensor is situated in the exhaust stream for determining a temperature of the exhaust gas at the reductant source. The intake mass air flow sensor measures an air mass flow entering the internal combustion engine. The control module is in communication with the reductant source, the temperature sensor, and the intake mass air flow sensor.