who knows if for sure which vacuum hose or hard plastic line is the main line/hose for feeding the heater a/c control panel in an 84 Maro V8 ? i have no vacuum at the ocntrol panel in the dash and i need ot know where its supposed ot be connected at the engine, on ported or manifold unported full time vac source ?

knowing color and where the main source line connects would be the best yet

thanks for anything !

 

The same thing happened to me, I have an '84 so it should be the same as yours. If I remember correctly, the line is that flexible plastic stuff and it's purple. Just look for a purple line going across the top of the firewall from the heater/a/c box to around the wiper motor area. I don't remember exactly what it connects to, mine was clogged somewhere so I just ran a new line from the vacuum going to the cruise control unit all the way to the part where the purple line goes into the CC unit. It works great now. You just want to make sure there is not too much vacuum going to the CC unit because it may cause the vent door motors to break.