Volkswagen is recalling 168,275 cars equipped with diesel engines because of a defect in the fuel injection system that could cause fuel leaks and fires. The recall affects certain 2009-2012 Jetta midsize cars, and some 2010 through 2012 Golf small cars, as well as some Audi A3 models from the 2010 through 2012 model years, the National Highway Traffic Safety Administration said Thursday on its website. All are equipped with 2-liter TDI diesel engines.