paddiee

I have a 97 ws-6 and the heat runs luke warm, sometimes cold. I flushed the heater core and also flushed the entire cooling system as well as bled the air out through the bleed valve on the upper water pump hose. The heat works for a day or 2 then runs cold again. I also have an issue with the air only coming out the defrost vents. I read elsewhere to check a 3 way vacuum connector on the passenger side. On top of that, there are 2 manifold vacuum lines that can cause this located on the passenger side. What, aside from solutions mentioned, can I do to resolve this? Much appreciated.