Ok im not sure what they are called but im trying to figure it out. The vaccum lines that come in the cab that control the vents hook in to (blank). The one that opens and shuts the face vents isn't working. When i turn it to feet or defrost it works but not face. Ive unhooked the arm that goes to the face control and made it stay on face all the time but ive tried to search for the part but havn't found it. 1999 1500 5.9L