[mrnickleye]

I by-passed the (not working) vsv when I got the car 5 years ago. I hooked the vac hose directly to the heater water valve.
Normal operation is that vacuum is always applied to it anyways.

The vsv 'only' shuts off vacuum when the temp controls are set to 65* (max. cooling, usually during a/c use).

If you hear a hiss with it hooked up to the water valve, then the valve is bad. Since you don't live in the extreme hot climate I do, then you could by-pass the valve by hooking the two hoses together with a splice tube from the parts store, to keep heater operation.

I always leave a pocket thermometer in the center vent, so I know what temp is coming out of the vents.

I always unplug the valve's vacuum line and golf tee it in the summer, so no water flows thru the heater core. This gives me about 4* colder air out the vents, which I really need for town driving when its over 100*.