Download Some 2005-2009 Mustang vehicles may exhibit a difficult to diagnose water leak in the front floor area. This may be caused by loose grommets and/or sealer skips around the cowl area, loose A-pillar window weatherstrip retainer, misaligned body harness grommet through the firewall, misaligned body harness grommet from the passenger door. ACTION: Follow the Service Procedure steps to correct the condition. SERVICE PROCEDURE NOTE: DO NOT REMOVE THE DASH OR THE DASH INSULATOR AT ANY TIME DURING THIS PROCEDURE. Water Leak Testing Procedure 1. To pressurize the cabin open trunk and remove the floor carpet. Remove the plastic tail panel cover. Remove side carpet push pins and move the carpet aside. Locate the body vents in the lower rear corners of the trunk (rear of wheel wells) and tape them off. Close the trunk. Place the blower motor on high. Turn air recirculation to off mode.