air coming thru vents..... hot air!!

[Stang_1973]

Ok well ive always had this problem just neve got around to fixing it.

The car originally came with AC however all the parts for ac are gone except for the controler in the dash and miscellaneous parts under the hood. theres no hosing or compressor. Anyway. as I drive the car air comes into the cab thru the dash vents and what seems to be the floor vents as well. Even when you put the controller in the off position air comes in. If you turn on the raise the fan setting it blows harder. Now the problem is that this air is frekin HOT!!! and with temps in the high 90's low 100s here in san antonio this is very stressing. I dont know if its air coming from the engine bay, or coming thru the cowl, passing thru the heater core and then coming thru the vents. ive cheked to make sure the flap for the heater core closes and it does but the air si still fricken hot! How can i check to make sure the controler is closing the vents? is there an way to close them mannually?

 

[Calponycarsmike]

I would check under the dash to see if the vents are closing all the way, sometimes the cables can get loose and not close it all the way, also depending on what is missing from your A/C system you could be drawing in hot air from the engine compartment. While you are down there check the seals on the vent doors. It is a pain rooting around under the dash, but it is your only option.

 

[Stang_1973]

How would I know if its drawing from the engine compartment? Thats what im afraid of, as the air is extremely hot.

 

[jcode68]

It's probably just leaking from the vents and the reason the air is hot is from the heater core. Mine does this too, but doesn't sound as bad as yours. I have seen people put shut off valves in the heater hose to shut the water flow going into the heater core during summer months. Do a search and you might be able to find a picture of this setup.

 

[Stang_1973]

Ah i see.. thanks.

 

[Platonic Solid]

If your car had A/C at one time, you should have a vacuum actuated shut-off valve in the right heater core feed hose near the firewall.

 

[Stang_1973]

I know for a fact that i do not have that. I saw something like that researching on the web to find a soloution to my problem. Now here goes, if i pick up one of these valves from the parts store, how does it go in? I have no idea how i would hook up the vacuum line...

 

[2+2GT]

I know for a fact that i do not have that. I saw something like that researching on the web to find a soloution to my problem. Now here goes, if i pick up one of these valves from the parts store, how does it go in? I have no idea how i would hook up the vacuum line...

The heater shut-off valve splices into the heater hose that comes from the intake manifold to the firewall, about at the back end of the valve cover. We should be able to find you the vacuum diagram to hook this up so it operates properly. The vacuum motors under the dash should not be circulating air unless you have set the controls to do so. Hot air should NOT be coming from the engine compartment unless someone has hacked holes.

 

[Platonic Solid]

Here's what mine looks like:

Here's where the vacuum hose exits the firewall to the heater control valve: