Abstract: Methods and systems are provided for an exhaust gas recirculation (EGR) system. In one example, a method includes determining a present EGR valve offset and an historical EGR valve offset and comparing the present EGR valve offset and the historical EGR valve offset to determine a presence of an EGR leak.

Abstract: A method and system for operating a vehicle that includes feedback of operating status of an engine starting system is described. In one example, the method inhibits automatic engine pull-down in response to feedback from an engine starting system that does not meet expectations. The system and method may provide diagnostics for the engine starting system.

Abstract: A method and system for operating a vehicle that includes feedback of operating status of an engine starting system is described. In one example, the method inhibits automatic engine pull-down in response to feedback from an engine starting system that does not meet expectations. The system and method may provide diagnostics for the engine starting system.

Abstract: Methods and systems are provided for controlling an aspirator shut-off valve in an engine of a hybrid vehicle. One example method includes opening the aspirator shut-off valve following a shut-down command to the engine when engine speed is between a first engine speed and a second engine speed, the first engine speed being lower than an idle speed and the second engine speed occurring before an imminent engine stop. The example method further includes not opening the aspirator shut-off valve between the first engine speed and the second engine speed if an oxygen content of an emission control device is at or near a threshold.

Abstract: Methods and systems are provided for controlling an aspirator shut-off valve in a boosted engine. One example method includes increasing an opening of the aspirator shut-off valve to allow motive flow through an aspirator in response to engine speed between a first, lower speed and a second, higher speed. As such, control of the aspirator shut-off valve may be simplified.

Abstract: Methods and systems are provided for controlling an aspirator shut-off valve in an engine of a hybrid vehicle. One example method includes opening the aspirator shut-off valve following a shut-down command to the engine when engine speed is between a first engine speed and a second engine speed, the first engine speed being lower than an idle speed and the second engine speed occurring before an imminent engine stop. The example method further includes not opening the aspirator shut-off valve between the first engine speed and the second engine speed if an oxygen content of an emission control device is at or near a threshold.

Abstract: A method for a hybrid-electric vehicle may comprise, while the hybrid-electric vehicle is moving and in an absence of fuel being directed to an engine, directing engine intake air through an ejector to supply vacuum to a brake booster independent of a brake booster vacuum.

Abstract: An aspirator coupled between an inlet of a compressor and an engine intake manifold may include sonic/supersonic expansion curves for both forward and reverse flow through the aspirator. Suction flow may enter a first entraining port coupling an ambient side of the aspirator with a vacuum source during reverse flow through the aspirator, whereas suction flow may enter a second entraining port coupling a manifold side of the aspirator with the vacuum source, the first entraining port counter sunk relative to a nominal slope of the aspirator to reduce flow disruption caused by the port during forward flow through the aspirator. A radial-flow aspirator shut-off valve arranged in series with the aspirator may be controlled to enable or disable motive flow through the aspirator, and motive flow may enter the valve in a direction perpendicular to a motive flow axis of the aspirator when the valve is open.

Abstract: Methods and systems are provided for controlling an aspirator shut-off valve in an engine of a hybrid vehicle. One example method includes opening the aspirator shut-off valve following a shut-down command to the engine when engine speed is between a first engine speed and a second engine speed, the first engine speed being lower than an idle speed and the second engine speed occurring before an imminent engine stop. The example method further includes not opening the aspirator shut-off valve between the first engine speed and the second engine speed if an oxygen content of an emission control device is at or near a threshold.

Abstract: Various methods for operating a wastegate are provided. In one example, a method of controlling a linked valve actuator system comprises adjusting the actuator near an end stop based on a learned uncertainty end stop region, the region based on operating conditions.

Abstract: Various methods for compensating variation in the geometry and position of linkages and valve seats in wastegate assemblies are provided. In one example, a method of operating a wastegate in an internal combustion engine comprises, at engine startup, placing a wastegate valve at a seat, recording a position of the seat and associating the seat position with one or more operating parameters, and modifying a position of a wastegate actuator based on the seat position throughout engine operation.

Abstract: Systems and methods are described for controlling an aspirator control valve in an engine. An example method comprises closing the aspirator control valve responsive to diagnosing a first engine degradation condition and opening the aspirator control valve in response to diagnosing a second engine degradation condition.

Abstract: Methods and systems are provided for controlling air ingestion in an engine during idle conditions. One example approach includes adjusting an opening of a common shut-off valve via an electronic controller, the common shut-off valve regulating each of motive flow through an aspirator and crankcase ventilation (CV) flow from a crankcase. As such, the common shut-off valve may be closed by the electronic controller during engine idle to cease each of the motive flow through the aspirator and the CV flow from the crankcase.

Abstract: An aspirator coupled between an inlet of a compressor and an engine intake manifold may include sonic/supersonic expansion curves for both forward and reverse flow through the aspirator. Suction flow may enter a first entraining port coupling an ambient side of the aspirator with a vacuum source during reverse flow through the aspirator, whereas suction flow may enter a second entraining port coupling a manifold side of the aspirator with the vacuum source, the first entraining port counter sunk relative to a nominal slope of the aspirator to reduce flow disruption caused by the port during forward flow through the aspirator. A radial-flow aspirator shut-off valve arranged in series with the aspirator may be controlled to enable or disable motive flow through the aspirator, and motive flow may enter the valve in a direction perpendicular to a motive flow axis of the aspirator when the valve is open.

Abstract: Various methods for operating a wastegate are provided. In one example, a method of adjusting a linked valve actuator system comprises applying, in addition to feedback position control adjustments, a non-harmonic oscillation to an actuator of the linked valve actuator system.

Abstract: An aspirator coupled between an inlet of a compressor and an engine intake manifold may include sonic/supersonic expansion curves for both forward and reverse flow through the aspirator. Suction flow may enter a first entraining port coupling an ambient side of the aspirator with a vacuum source during reverse flow through the aspirator, whereas suction flow may enter a second entraining port coupling a manifold side of the aspirator with the vacuum source, the first entraining port counter sunk relative to a nominal slope of the aspirator to reduce flow disruption caused by the port during forward flow through the aspirator. A radial-flow aspirator shut-off valve arranged in series with the aspirator may be controlled to enable or disable motive flow through the aspirator, and motive flow may enter the valve in a direction perpendicular to a motive flow axis of the aspirator when the valve is open.

Abstract: Methods and systems are provided for controlling an aspirator shut-off valve in an engine of a hybrid vehicle. One example method includes opening the aspirator shut-off valve following a shut-down command to the engine when engine speed is between a first engine speed and a second engine speed, the first engine speed being lower than an idle speed and the second engine speed occurring before an imminent engine stop. The example method further includes not opening the aspirator shut-off valve between the first engine speed and the second engine speed if an oxygen content of an emission control device is at or near a threshold.

Abstract: Methods and systems are provided for controlling air ingestion in an engine during idle conditions. One example approach includes adjusting an opening of a common shut-off valve via an electronic controller, the common shut-off valve regulating each of motive flow through an aspirator and crankcase ventilation (CV) flow from a crankcase. As such, the common shut-off valve may be closed by the electronic controller during engine idle to cease each of the motive flow through the aspirator and the CV flow from the crankcase.

Abstract: Systems and methods are described for controlling an aspirator control valve in an engine. An example method comprises closing the aspirator control valve responsive to diagnosing a first engine degradation condition and opening the aspirator control valve in response to diagnosing a second engine degradation condition.

Abstract: Methods and systems are provided for controlling an aspirator shut-off valve in a boosted engine. One example method includes increasing an opening of the aspirator shut-off valve to allow motive flow through an aspirator in response to engine speed between a first, lower speed and a second, higher speed. As such, control of the aspirator shut-off valve may be simplified.