Find replacement 1979-1993 Mustang EGR valves to fix your rough idle or check engine light at 5.0 Resto. A malfunctioning EGR valve can cause your Fox Body to buck on acceleration, run rough, and decrease your gas mileage. Late Model Restoration offers Motorcraft and Ford replacement EGR valves and gasket kits to keep your Mustang running right. Pick up one today for your 1986, 1987, 1988, 1989, 1990, 1991, 1992, or 1993 Fox Body Mustang.