When my 93 3.8 is cold & hot I can feel high pressure in the upper rad hose to the thermostat. Is this normal or a sign that the termostat may be stuck close???? I still get good heat and don't think the vehicle is overheating. I say "don't think" because my temperature gauge needle is usually resting at the bottom of the gauge, but periodically bounces around. Why is that???

remove the radiator cap when the engine is cold - watch for bubles coming up - this sounds like a good case for the ever cronic blown head gaskets in the 3.8