KR81

So as the title says, I get constant warm air at my feet with selector on cold and with fan off. It also appears that I have no vacuum at the heater valve as both hoses (into and out of the heater core) are constantly hot. I've pulled the hose from the valve while the car is running and checked it for vacuum with selector on cold and hot. I believe it's meant to have vacuum with selector on hot but none of the old threads I've found have confirmed that.
I've been searching the board and reading all the posts relating to my issue but either not coming up with a solution or old posts just have no resolution. I've recently replaced some of the old vacuum lines, not all.
I also have cruise control that does not function, possibly related ?
Wondering where the line that goes into the valve gets its vacuum? It disappears down behind the distributor.
Appreciate any input.
1988 305 TA

KR81

Anyone ?

3rdgenzroc

The heater valve does need vacuum to divert the coolant (from valve to heater core or valve to radiator) and it's not in the heater core (it should be next to the PS valve cover). If everything is off, it should not pull in to the heater core, but go to the radiator. Sounds like the valve is not working. Check to see if it has vacuum. If it doesn't obviously you have a vacuum problem. If it does, your diverter valve is bad. You need to look for a diagram of the vacuum routing for your year/engine of the car for the HVAC and trace down your leak if it is vacuum. I would replace all of the rubber tubing while your at it since it is old and needs it anyway. If your controls are not working after you have proper vacuum everywhere, then there is probably an issue with the control selector itself. Again, search for this and you will find how to fix it (vids and threads) or where to source a repop part since it is another discontinued part. There is ways to bypass it also if your not into fixing it, by rerouting your hoses too. Hope this helps getting you started in the right direction.