So yesterday I did a seafoam job so I had to unplug the upper intake vac hose to put the seafoam in. Today I started my car and turned on the A/C only to find all the air coming though the defrost windshield vents and not the dash vents. The air came though the same spot no matter if I tried A/C, defrost, Mix, or floor, all though defrost! I looked under the hood and dont see anything unpluged and the only hose I did unplug is back where it should be. Please help.

Thanks,
Matthew

 

Check the vacuum hose that runs along the firewall, it may have a slice in it, or loose off the canister on the drivers side by the brake booster. I used to own a 95, had that problem before.

 

Ok, I looked over all the hoses and didnt see anything wrong or split. My question is do we have a butterfly valve in the dash that controls where the A/C air goes once its inside the car that could be caught in the open or closed position causing all the air to go to one place?

Thanks,
Matthew

 

I don't believe so, but I'm not totally positive on that. Did you find the main host that runs along the firewall, it's like a 1/2 inch vacuum line if I remember correctly. It connects to a plastic white fitting.

 

Yeah, I found it and everything looks good. Nothing moves, no splits in any hoses. This is so annoying and its 104 in cali today I need my air back!

Matthew

 

Does this hose have good vacuum?

Smitty

 

Sometimes it's hard to detect a bad line, it has to be that hose, or the control panel(the actual unit that controls the floor, defrost, etc) in the vehicle is bad. My money is still on that hose.

 

To the best of my knowledge, most of the parts controling the flow of A/C are under the dash. I *think* that they can be accessed by simply pulling off the center consonle piece (the whole section w/ A/C switches, stereo cutout, and 3 buttons that are in front of the shifter). That piece of plastic simply pops out of the spot its in, so be gentle, and just tug a little at a time.

Not sure if what you're looking for will be back there, but it's a start.

 

Azrael, you’re not far off. There are three modules that control your air coming out. The culprit is a valve behind the radio. I have the same issue right now. I took my car to a mechanic and he said I could either have the ac coming out the defrost or heat! I chose heat for the winter. I found the part numbers and location of the module but have misplaced it and I’m looking for it again. I Solent the whole last year in triple digits taking the das apart in a salvage yard and could find the module, even with a picture and knowing the area it’s in. I am going to try and see if that mechanic is still working at this shop because he knows exactly where it is. I call Ford and every truck, Mustang and all the parts stores I could find searching for this part. They don’t make it and I couldn’t find anyone in the US that has one. So I’m hoping the mechanic can physically show me exactly where it is an I will get some from the salvage. I know your post is like 4 years old but maybe it will help someone in 2023. If the original question writer if you are still on here, did you ever find your issue? Thanks