Abstract: An exhaust aftertreatment system includes a particulate filter element and a particulate matter sensor that is disposed to monitor the exhaust gas feedstream downstream of the particulate filter element. A method for monitoring the exhaust gas feedstream includes determining a temperature associated with the particulate matter sensor and monitoring engine operation and the exhaust aftertreatment system. A magnitude of ammonia is determined in the exhaust gas feedstream proximal to the particulate matter sensor based upon the monitoring of the engine operation and the exhaust aftertreatment system. An initial reading is determined from the particulate matter sensor and is adjusted based upon the magnitude of ammonia in the exhaust gas feedstream proximal to the particulate matter sensor and the temperature of the particulate matter sensor. A magnitude of particulate matter in the exhaust gas feedstream is determined based upon the adjusted initial reading from the particulate matter sensor.

Abstract: A method of controlling a rate of warm-up of an internal combustion engine fluidly connected to an exhaust system is disclosed. The method includes identifying a cold-start of the engine. The method also includes regulating, in response to the identified cold-start of the engine, an exhaust pressure modulation (EPM) valve arranged in a main exhaust passage of the exhaust system. The main exhaust passage channels engine exhaust gas to the ambient. Such regulation of the EPM valve will restrict a flow of the engine exhaust gas to the ambient and increase exhaust gas backpressure in the exhaust system up to a predetermined pressure value. Furthermore, the subject regulation of the EPM valve will increase a load on and the rate of warm-up of the engine. A vehicle having an engine and a controller programmed to control a rate of the engine's warm-up of according to the method is also disclosed.

Abstract: A direct fuel injection internal combustion engine fluidly coupled to an exhaust aftertreatment system is described and includes a plurality of fluidly coupled exhaust purifying devices and an exhaust gas sensor. A method of controlling the engine includes, activating, via a heater controller, a heating element of the exhaust gas sensor in response to starting the internal combustion engine. An exhaust gas feedstream is monitored to determine a temperature of the exhaust gas sensor. Engine control to effect heating of one of the exhaust purifying devices is permitted only when a temperature of the exhaust gas sensor is greater than a threshold temperature.

Abstract: An exhaust aftertreatment system includes a particulate filter element and a particulate matter sensor that is disposed to monitor the exhaust gas feedstream downstream of the particulate filter element. A method for monitoring the exhaust gas feedstream includes determining a temperature associated with the particulate matter sensor and monitoring engine operation and the exhaust aftertreatment system. A magnitude of ammonia is determined in the exhaust gas feedstream proximal to the particulate matter sensor based upon the monitoring of the engine operation and the exhaust aftertreatment system. An initial reading is determined from the particulate matter sensor and is adjusted based upon the magnitude of ammonia in the exhaust gas feedstream proximal to the particulate matter sensor and the temperature of the particulate matter sensor. A magnitude of particulate matter in the exhaust gas feedstream is determined based upon the adjusted initial reading from the particulate matter sensor.

Abstract: A method of controlling a rate of warm-up of an internal combustion engine fluidly connected to an exhaust system is disclosed. The method includes identifying a cold-start of the engine. The method also includes regulating, in response to the identified cold-start of the engine, an exhaust pressure modulation (EPM) valve arranged in a main exhaust passage of the exhaust system. The main exhaust passage channels engine exhaust gas to the ambient. Such regulation of the EPM valve will restrict a flow of the engine exhaust gas to the ambient and increase exhaust gas backpressure in the exhaust system up to a predetermined pressure value. Furthermore, the subject regulation of the EPM valve will increase a load on and the rate of warm-up of the engine. A vehicle having an engine and a controller programmed to control a rate of the engine's warm-up of according to the method is also disclosed.

Abstract: A vehicle includes an engine having cylinders in fluid communication with an intake air flow, a mass air flow (MAF) sensor positioned with respect to the intake air flow which outputs a pulse train signal describing the frequency of the intake air flow, and a controller. The controller includes a calibrated non-linear conversion curve recorded in memory. The controller executes a method to convert the frequency data into a corresponding mass air flow using the calibrated non-linear conversion curve, determines the instantaneous mass air flow value at each leading or trailing edge of the pulse train signal, and accumulates the instantaneous mass air flow values over a calibrated duration. A time-weighted average of the accumulated mass air flow values is then used to execute a control action. The controller includes a host computer device and memory storing the curve and instructions for executing the method.

Abstract: A method for monitoring an internal combustion engine includes monitoring thermal efficiency in a heat exchanger of an exhaust gas recirculation (EGR) system with a flow control valve commanded to a first, open state and monitoring thermal efficiency in the heat exchanger with the flow control valve commanded to a second, closed state. The flow control valve is evaluated based upon the monitored efficiencies.

Abstract: A turbocharger controller includes a turbocharger compressor temperature module having a compressor inlet air temperature input, and a turbocharger compressor pressure module including a compressor inlet pressure input and a compressor outlet pressure input. A memory module includes a compressor outlet temperature calibration map and a compressor pressure ratio look-up table. A turbocharger boost pressure ratio control module is operatively connected to the turbocharger compressor temperature module, the turbocharger compressor pressure module, and the memory module. The turbocharger boost pressure ratio control module is configured to selectively compare compressor outlet pressure and compressor inlet pressure with values in the compressor ratio look-up table to determine a turbocharger boost pressure set point establishing a desired compressor outlet temperature.

Abstract: A method of controlling exhaust braking in an internal combustion engine is disclosed. The engine includes an exhaust system, an exhaust pressure modulation valve, and a variable geometry turbocharger having adjustable vanes. The method includes restricting a flow of the exhaust gas through the exhaust system via a first partially-closed position of the valve. The valve's first partially-closed position increases the exhaust backpressure in the engine up to a first pressure value and generates a first stage of exhaust braking by the engine. The method also includes, following the increase of exhaust backpressure in the engine up to the first pressure value, restricting a flow of the exhaust gas through the turbocharger via closing the turbocharger's adjustable vanes. The closing of the turbocharger's adjustable vanes increases the exhaust backpressure up to a second pressure value in the exhaust system and generates a second stage of exhaust braking by the engine.

Abstract: A method for assessing a cold start emission reduction (CSER) strategy applied to an engine system is provided. The method determines a first accumulation value based on an estimated output signal that would result from applying a first control command to the engine system. The method determines a second accumulation value based on a measured output signal resulting from applying a second control command that implements the CSER strategy to the engine system. The method compares the first accumulation value and the second accumulation value. The method determines whether the applying the second command to the engine system achieved a performance threshold of the CSER strategy based on the comparing.

Abstract: A method of controlling exhaust braking in an internal combustion engine is disclosed. The engine includes an exhaust system, an exhaust pressure modulation valve, and a variable geometry turbocharger having adjustable vanes. The method includes restricting a flow of the exhaust gas through the exhaust system via a first partially-closed position of the valve. The valve's first partially-closed position increases the exhaust backpressure in the engine up to a first pressure value and generates a first stage of exhaust braking by the engine. The method also includes, following the increase of exhaust backpressure in the engine up to the first pressure value, restricting a flow of the exhaust gas through the turbocharger via closing the turbocharger's adjustable vanes. The closing of the turbocharger's adjustable vanes increases the exhaust backpressure up to a second pressure value in the exhaust system and generates a second stage of exhaust braking by the engine.

Abstract: A direct fuel injection internal combustion engine fluidly coupled to an exhaust aftertreatment system is described and includes a plurality of fluidly coupled exhaust purifying devices and an exhaust gas sensor. A method of controlling the engine includes, activating, via a heater controller, a heating element of the exhaust gas sensor in response to starting the internal combustion engine. An exhaust gas feedstream is monitored to determine a temperature of the exhaust gas sensor. Engine control to effect heating of one of the exhaust purifying devices is permitted only when a temperature of the exhaust gas sensor is greater than a threshold temperature.

Abstract: A method of adapting operation of a variable geometry turbocharger having a variable position vane mechanism with movable vanes is disclosed. The method includes performing at time T1 a vane sweep between open-limit and closed-limit positions to identify an initial range of movement of the mechanism and storing in controller's memory the initial range of movement. The method additionally includes performing at time T2 a vane sweep between the open-limit and closed-limit positions to identify a current range of movement of the mechanism and storing in controller's memory the current range of movement. The method also includes comparing the current range with the initial range. Furthermore, the method includes replacing in controller's memory the initial range with the current range if the current range is equal to or greater than a predetermined range to thereby adapt the operation of the turbocharger to the mechanism's wear between T1 and T2.

Abstract: A method for monitoring an internal combustion engine includes monitoring thermal efficiency in a heat exchanger of an exhaust gas recirculation (EGR) system with a flow control valve commanded to a first, open state and monitoring thermal efficiency in the heat exchanger with the flow control valve commanded to a second, closed state. The flow control valve is evaluated based upon the monitored efficiencies.

Abstract: A system and method of operating an exhaust gas recirculation (EGR) system of a vehicle includes controlling an EGR valve actuable between an EGR enabled position and an EGR disabled position, such that with the EGR valve in the EGR enabled position a portion of exhaust gas emitted from an engine is directed through an EGR cooler for recirculation into the engine, and with the EGR valve in the EGR disabled position the exhaust gas is not recirculated through the engine. An EGR coolant temperature is predicted based on measured engine speed, vehicle speed, outside ambient temperature, and commanded fuel level of the vehicle. The EGR valve is actuated to the EGR disabled position when the predicted EGR coolant temperature is equal or greater than an EGR coolant temperature threshold. The EGR coolant temperature is predicted without direct measurement of engine coolant temperature.

Abstract: A method for assessing a cold start emission reduction (CSER) strategy applied to an engine system is provided. The method determines a first accumulation value based on an estimated output signal that would result from applying a first control command to the engine system. The method determines a second accumulation value based on a measured output signal resulting from applying a second control command that implements the CSER strategy to the engine system. The method compares the first accumulation value and the second accumulation value. The method determines whether the applying the second command to the engine system achieved a performance threshold of the CSER strategy based on the comparing.

Abstract: A method for adjusting an oxygen sensor measurement within an exhaust gas feedstream output from an internal combustion engine based on humidity includes monitoring relative humidity of ambient air obtained from a humidity sensor. Specific humidity at the oxygen sensor is modeled based on the relative humidity. The oxygen sensor measurement is adjusted based on the modeled specific humidity at the oxygen sensor.

Abstract: A method of adapting operation of a variable geometry turbocharger having a variable position vane mechanism with movable vanes is disclosed. The method includes performing at time T1 a vane sweep between open-limit and closed-limit positions to identify an initial range of movement of the mechanism and storing in controller's memory the initial range of movement. The method additionally includes performing at time T2 a vane sweep between the open-limit and closed-limit positions to identify a current range of movement of the mechanism and storing in controller's memory the current range of movement. The method also includes comparing the current range with the initial range. Furthermore, the method includes replacing in controller's memory the initial range with the current range if the current range is equal to or greater than a predetermined range to thereby adapt the operation of the turbocharger to the mechanism's wear between T1 and T2.

Abstract: A method of controlling a diesel engine includes sensing a speed of the diesel engine, and closing a throttle of the diesel engine when the sensed speed of the diesel engine is equal to or greater than a maximum allowable engine speed to prevent oxygen from entering an intake manifold of the diesel engine, thereby preventing combustion and stopping the operation of the diesel engine. An Exhaust Gas Recirculation (EGR) valve is actuated to regulate circulation of exhaust gas from the diesel engine through the intake manifold to control pressure within the intake manifold to prevent damage to other engine components from excessive positive or negative pressure.

Abstract: A system and method of operating an exhaust gas recirculation (EGR) system of a vehicle includes controlling an EGR valve actuable between an EGR enabled position and an EGR disabled position, such that with the EGR valve in the EGR enabled position a portion of exhaust gas emitted from an engine is directed through an EGR cooler for recirculation into the engine, and with the EGR valve in the EGR disabled position the exhaust gas is not recirculated through the engine. An EGR coolant temperature is predicted based on measured engine speed, vehicle speed, outside ambient temperature, and commanded fuel level of the vehicle. The EGR valve is actuated to the EGR disabled position when the predicted EGR coolant temperature is equal or greater than an EGR coolant temperature threshold. The EGR coolant temperature is predicted without direct measurement of engine coolant temperature.