Project 5.GO!

When I accelerate the air from my AC vents gets diverted to the defroster vents, and it comes back when I get to cruising speed.

This is a vacuum thing, isn't it? What is doing this?

DeathRattle

Maybe this info might help. My heat worked on my 95 but the fan only blew the defrosters regardless of the fan **** setting. There was a line coming from the firewall on the passenger side that had been disconnected. I ran a vacuum hose to it from the intake and now all my fan **** settings work fine. I'd say look for that line and make sure it's connected.

Project 5.GO!

I remember that happening a while back when the original hard plastic line broke. I reconnected it with aquarium tubing, tucked under the pinch weld so it wouldnt look hillbilly... LOL'

Maybe it's compressing under heavy vacuum and pinching shut. The reason I went with the aquarium tube is that discount doesnt have the sleek slim plastic hardline that Ford used, they have regular vacuum tube, about the same outer diameter as my pinky, which would look huge compated to the tree connection and the connection on the other side, and has no flex to let me hide it. Oh well, I tried making it look nice, time to give ugly a try.

Bubba 95SN

There is smaller vacum line available. Slipped a short piece(1") on my brittle line to hvac control. Seen the plastic line at NAPA(memory?). The loss of vacum sends system to its default position, defrost.