Remove husks; wash and clean corn. Place each ear on double thickness of heavy duty foil; wrap snugly. Preheat gas grill. Cook, with cover down, on medium setting 25 to 30 minutes, turning frequently.
Pull husks away from corn, leaving husks attached. Remove silks, push husks back in place, tying with string to hold husks firmly around corn. Soak corn in cold water for 30 minutes. Preheat gas grill. Remove corn from water and place on grid. Cook, with cover down, on medium setting 25 minutes or until done, turning frequently.