Good suggestions - Thank you. I will check out the vacuum situation and let you know. Before I removed the heater control valve I did notice the vacuum actuated arm appeared to move through it's full range of motion when I changed the temperature selector. I suppose the vacuum to the doors could be ...

92 944, 88K mi, heat is just not very hot. Removed heater control valve and put in straight connector for full flow, flushed heater core - great flow in both directions, new thermostat, inlet and outlet hose to heater core nice and hot, plenty of coolant, good air flow from vents - although not alwa...