Hyundai Motor America (Hyundai) is recalling certain model year 2011-2012 Sonata vehicles manufactured December 11, 2009, to April 12, 2012 at Hyundai Motor Manufacturing Alabama and equipped with either a 2.0 liter or 2.4 liter Gasoline Direct injection engine. In the affected vehicles, metallic debris may not have been fully removed during manufacturing of the engine crankshaft. If the debris was not completely removed, oil flow may be restricted through the connecting rod bearings, causing connecting rod damage. A worn connecting rod bearing will produce a metallic, cyclic knocking noise from the engine and possible engine failure.