Recently I took it in for an oil change. The A/C hadn't been working correctly before the change (Cold air was only blowing from the defrost vents) and after the change the cold air blew out of the normal vents. It worked only for a couple of minutes then started to blow out of the defrost vents again. Someone said it might be the vaccum hose but I don't know where they are. Could someone tell me so I can check it out?

 

I don't know if it's the same on v6's, but on my GT it is a red tube that connects just downstream of the throttle body. The tube has a small diameter. If I saw a picture of your engine bay I could probably point it out to ya.

 

the same thing happened to my 98 stang and it has been killing for a like 2 years nowwhere can i get it fixed and is it something i can do