Abstract: A skip fire engine controller and method of control is described wherein during transitions from a first firing density to a second firing density, a firing density and a pumping density are separately set so as to balance the conflicting demands of (a) torque control, (b) Noise, Vibration and Harshness (NVH), (c) air flow through the engine and (d) air-fuel ratio.

Abstract: A system and method of integrating an engine having dynamic skip fire control with an exhaust gas recirculation system in a turbocharged internal combustion engine is described. An engine control system determines an appropriate firing pattern based at least in part on a desired exhaust gas recirculation flow rate. Signals from sensors in the intake manifold and exhaust system may also be used as part of a feedback loop to determine a desired exhaust gas recirculation flow rate.

Abstract: Controllers and methods for managing transitions into and/or out of a cylinder cut off mode are described. In some embodiments, a skip fire based transition into a cylinder cut off mode is used in which the fraction of working cycles that are fired is gradually reduced to a threshold firing fraction. Once the threshold firing fraction has been reached, all of the working chambers are deactivated.

Abstract: Using machine learning for cylinder misfire detection in a dynamic firing level modulation controlled internal combustion engine is described. In a classification embodiment, cylinder misfires are differentiated from intentional skips based on a measured exhaust manifold pressure. In a regressive model embodiment, the measured exhaust manifold pressure is compared to a predicted exhaust manifold pressure generated by neural network in response to one or more inputs indicative of the operation of the vehicle. Based on the comparison, a prediction is made if a misfire has occurred or not. In yet other alternative embodiment, angular crank acceleration is used as well for misfire detection.

Abstract: A skip fire engine controller and method of control is described wherein during transitions from a first firing density to a second firing density, a firing density and a pumping density are separately set so as to balance the conflicting demands of (a) torque control, (b) Noise, Vibration and Harshness (NVH), (c) air flow through the engine and (d) air-fuel ratio.

Abstract: A skip fire control that relies on a combination of a torque request, exhaust temperature, and air-fuel ratio in determining firing density is described. Also, skipped firing opportunities may either pump or not pump air into an exhaust system, allowing an exhaust gas temperature in the exhaust system to be controlled or modulated. The present invention is also related to Dynamic Skip Fire (DSF), where a decision to either fire or skip cylinders is made every firing opportunity.

Abstract: Using machine learning for misfire detection in a Dynamic firing level modulation controlled internal combustion engine is described. A neural network is used to calculate expected crank acceleration from various inputs, including the dynamically defined cylinder skip fire sequence. The output of the neural network is then compared to a signal indicative of the measured crank acceleration. Based the comparison, a prediction is made if a misfire has occurred or not. In alternative embodiment, the neural network is expanded to include the measured crank acceleration as an additional input. With the latter embodiment, the neural network is arranged to directly predict misfire events.

Abstract: A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.

Abstract: A skip fire engine controller and method of control is described wherein during transitions from a first firing density to a second firing density, a firing density and a pumping density are separately set so as to balance the conflicting demands of (a) torque control, (b) Noise, Vibration and Harshness (NVH), (c) air flow through the engine and (d) air-fuel ratio.

Abstract: In this board game, players take turns being the Chief and rating their level of agreement with prompts such as: “For $1000, I would be willing to wear the same underwear for a week without washing it.” The opinions are guessed using a scale from 1 (“Frostbite!—Completely Disagree”) to 10 (“All Ablaze!—Completely Agree”). Before the Chief reveals his/her rating, all of the other players guess the Chief's response using secret voting tokens, and all the votes are revealed simultaneously. At the end of the round, the closest matches score victory points. With over 700 cards already written, the prompts cover an enormous range of topics from intimate to hilarious, from every-day to fantastical, from family-oriented to party-friendly. Since the point system requires collecting points of all colors in order to win, you cannot win simply by knowing one other player extremely well.

Abstract: A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.

Abstract: A skip fire control that relies on a combination of a torque request, exhaust temperature, and air-fuel ratio in determining firing density is described. Also, skipped firing opportunities may either pump or not pump air into an exhaust system, allowing an exhaust gas temperature in the exhaust system to be controlled or modulated. The present invention is also related to Dynamic Skip Fire (DSF), where a decision to either fire or skip cylinders is made every firing opportunity.

Abstract: A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.

Abstract: Using machine learning for misfire detection in a Dynamic firing level modulation controlled internal combustion engine is described. A neural network is used to calculate expected crank acceleration from various inputs, including the dynamically defined cylinder skip fire sequence. The output of the neural network is then compared to a signal indicative of the measured crank acceleration. Based the comparison, a prediction is made if a misfire has occurred or not. In alternative embodiment, the neural network is expanded to include the measured crank acceleration as an additional input. With the latter embodiment, the neural network is arranged to directly predict misfire events.

Abstract: A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.

Abstract: A variety of methods and arrangements for detecting misfire and other engine-related errors are described. In one aspect, a window is assigned to a target firing opportunity for a target working chamber. There is an attempt to fire a target working chamber during the target firing opportunity. A change in an engine parameter (e.g., crankshaft angular acceleration) is measured during the window. A model (e.g., a pressure model) is used to help determine an expected change in the engine parameter during the target firing opportunity. Based on a comparison of the expected change and the measured change in the engine parameter, a determination is made as to whether an engine error (e.g., misfire) has occurred.

Abstract: A variety of methods, diagnostic modules and other arrangements for detecting air induction faults during operation of an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored with the intake pressure being read for each induction opportunity. Induction faults may be detected based at least in part on a comparison of the manifold pressure readings for sequential induction opportunities. In some embodiments, an induction fault is identified when the difference between the manifold pressure associated with an induction opportunity and the immediately preceding induction opportunity exceeds an induction fault threshold.

Abstract: A variety of methods, diagnostic modules and other arrangements for detecting air induction faults during operation of an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored with the intake pressure being read for each induction opportunity. Induction faults may be detected based at least in part on a comparison of the manifold pressure readings for sequential induction opportunities. In some embodiments, an induction fault is identified when the difference between the manifold pressure associated with an induction opportunity and the immediately preceding induction opportunity exceeds an induction fault threshold.

Abstract: Methods and systems are described for detecting valve actuation faults in internal combustion engines operating in a skip fire operational mode. In one aspect, for each skip fire working cycle, an expected exhaust pressure is determined for a time period corresponding to a potential exhaust event. One or more exhaust gas pressure sensors are then used to measure an actual exhaust pressure during the potential exhaust period. The actual exhaust pressure is compared to the expected exhaust pressure to determine whether a valve actuation fault has occurred. A variety of valve actuation faults can be identified using the described approach. In some embodiments pressure sensors are deployed in the runners of the exhaust manifold.

Abstract: A variety of methods and arrangements for detecting failure of the commanded air induction in an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored. An air induction event generates a fluctuation in the intake manifold pressure, which is recorded. The signal is processed through a diagnostic filter to help determine whether the actual induction matched the commanded induction. In other embodiments, measured crankshaft acceleration is compared with estimated crankshaft acceleration. If the two quantities differ by a threshold amount an induction fault is detected. The two detection methods may also be combined. The describe approaches are particularly well suited for use in engines operating in a skip fire mode with cylinder deactivation and/or a dynamic firing level modulation mode.