RepairPal Certified shops can diagnose and repair your 1999 Ford Expedition. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
if you have manual claimet control you may have vacum line from the engine problem or if its digital you may have bad cotrol or bend door motor good luck
hopefully u have gotten this fixed by now... but I had a similar problem replaced a lot of things needlessly. eventually replace the EACT unit itself the dial to the far rt just stopped working one day... Got a use one from a wreaking yard though. a new one for 1999 ford expedition would have cost $700 +. hope that helped. went an entire winter with no heat and it wasn't nice !!!
hopefully u have gotten this fixed by now... but I had a similar problem replaced a lot of things needlessly. eventually replace the EACT unit itself the dial to the far rt just stopped working one day... Got a use one from a wreaking yard though. a new one for 1999 ford expedition would have cost $700 +. hope that helped. went an entire winter with no heat and it wasn't nice !!!