Looking for schematics for the vacuum lines. Im looking for the purple and gray vacuum lines that come off the left side of the control panel. The lines go under the dash and attached to a main feed vacuum line? Yes, No?
Someone has rigged mine prior to me owning it, taping the lines to a main vacuum source, is there suppose to be a one way valve at the end? the problem im having is the vacuum valve that always goes bad in the control panel is hissing when i switch mine over to heat, i have tried 3 different ones and they all hiss. dont think thats the issue.
Lots of rambling i no, hope it makes sense.

 

Purple is the vacuum supply. Gray is the heater control valve. Sounds like someone in your car's past was an idiot.