Vacuum Heating Cooling Diagram

I have a 71 Charger, it has a vacuum controlled heating and cooling system.
Aparently there is a problem with either the way it is hookes up, or a vac leak not allowing it to work properly.

does anyone know where I can find a Vacuum Heating Cooling Diagram, so that I can replace my lines and hook things up correctly? :confused:

Thanks,
Scott :parts book:

Probably one in a factory service manual. As far as a leak goes, assuming your controls have pushbuttons, there is a possibility the back of the vacuum switch has separated. Happens a lot

You should have a vacumn line running off back of your intake inside to your vacumn control on your heater and ac controls, there should also be a small valve in that line right before it hooks up to heater and ac controls, check and make sure this is hooked up, there is a big vacumn plug that plugs on your heater /ac control, and also up behind your radio is a vacumn pod which opens and closes doors, check it out. First thens first, make sure you have vacumn to it.