Abstract: An engine system and method for variable valve lift (VVL) diagnostic techniques are provided. In one exemplary implementation, the techniques include receiving, at a controller, a camshaft position signal indicative of detected edges of teeth of a camshaft toothed member that is coupled to a camshaft of an engine. The camshaft is configured to actuate a VVL system, which is configured to control a lift of a valve of the engine. The techniques also include calculating, at the controller, a camshaft speed signal indicative of a rotational speed of the camshaft based on the camshaft position signal. A valve stuck index (VSI) value is then calculated, at the controller, based on the camshaft speed signal. The techniques also include determining, at the controller, whether the valve is stuck based on a comparison of the VSI value to a predetermined threshold.

Abstract: A cylinder head gasket for an engine is provided. The gasket includes an opening positioned in a gasket substrate and arranged to align with an engine oiling circuit passage to allow oil to flow from a cylinder block through the gasket to a cylinder head. The gasket further includes a filter element attached to the gasket relative to the opening and arranged to provide a barrier to debris in the oiling circuit.