Abstract: Various methods and systems are provided for diagnosing an exhaust gas recirculation valve based on crankcase pressure. In one example, a method comprises indicating a condition of a valve disposed in a first exhaust passage downstream from a cylinder exhaust valve based at least in part on a crankcase pressure.

Abstract: Various methods and systems are provided for diagnosing an exhaust gas recirculation valve based on crankcase pressure. In one example, a method comprises indicating a condition of a valve disposed in a first exhaust passage downstream from a cylinder exhaust valve based at least in part on a crankcase pressure.

Abstract: Various methods and systems are provided for blocking backflow of exhaust through an exhaust gas recirculation system. In one embodiment, a method comprises flowing exhaust gas through an exhaust gas recirculation (EGR) passage in a first direction from at least a first cylinder group of an engine to an intake manifold of the engine, the exhaust gas flowing in the first direction through a filter arranged in the EGR passage prior to reaching the intake manifold, and blocking flow of gas through the filter in a second, opposite direction with a mechanical one-way valve positioned in the EGR passage between the filter and the intake manifold.

Abstract: Various methods and systems are provided for controlling a hydraulically actuated engine valve. In one example, a system includes a hydraulically actuated engine valve and an engine having a first hydraulic system. The system further includes a second hydraulic system, which is separate from the first hydraulic system, and where the second hydraulic system provides fluid pressure to actuate the valve.

Abstract: Various methods and systems are provided for blocking backflow of exhaust through an exhaust gas recirculation system. In one embodiment, a method comprises flowing exhaust gas through an exhaust gas recirculation (EGR) passage in a first direction from at least a first cylinder group of an engine to an intake manifold of the engine, the exhaust gas flowing in the first direction through a filter arranged in the EGR passage prior to reaching the intake manifold, and blocking flow of gas through the filter in a second, opposite direction with a mechanical one-way valve positioned in the EGR passage between the filter and the intake manifold.

Abstract: Various methods and systems are provided for controlling a hydraulically actuated engine valve. In one example, a system includes a hydraulically actuated engine valve and an engine having a first hydraulic system. The system further includes a second hydraulic system, which is separate from the first hydraulic system, and where the second hydraulic system provides fluid pressure to actuate the valve.