I have a 98 stang and the A/C will only blow thru the top defrost vent regardless of what setting I have it on. Any guesses or knowledge to what could be causing this?

Thanks

 

Vac. leak or defective switch. Ford has them default to defrost for safety if the system fails in the winter.

 

go to the firewall on the passenger side and locate the where the coolant lines go through. There in that cluster of crap going in/out is a single vac line that goes across the back of the firewall to the vac tree on the drivers side. It will more then likely be dangling down and just need a small connector or extended an inch or two. That vac line goes to the blend door to control it.

 

The line ttocs is taking about is a thin plastic tube. They tend to get brittle and break as the car ages. If it is broken, you can splice the two ends together with a rubber hose with an inner diameter a little smaller then the plastic tube (to make a good seal). I got one from my local autoparts store when the tube broke on my wifey's '98 mustang.

 

Hell yea! Thanks! I'm at work right now but I'll under the dash as soon as I get off!