Overheating...., Diagnose my problem? Options

[95GTCelica]

Alright 6GC People I need your help...

Today after driving for about fifteen/twenty minutes I parked and noticed that the temp gauge read above the red line and the H. Popped the hood and heard gurgeling coming from the radiator with some overflow. I let it cool down for an hour then came back and drove around the block a couple times. I noticed that the temperature goes through the roof when it starts and slowly climbs. But when i hit about 40mph it cools down to about 3/4 of the way and when i stop it goes straight back up. I had a similar problem like this before and it was a bad water pump which was replaced a few weeks ago. Today there was no coolant on the ground just the few drops that spilled from the overflow. The engine seemed to be running fine and I wouldnt have noticed anything wrong with it unless i looked at the temp gauge. So can anyone help me? Any ideas? I'm stumped.

[lubu]

Another theory is that you might have a clog within the engine's block and that stops the water from carrying the heats and dissipates them. If this is the case then even though your fans are on, when stop the temp will still rises up coz the heats are not being dissipate by the radiator and still trapped inside the engine's block, with the car moving the air flowing into the engine dissipates some of the heat and hence the temp returns to normal.

But for your sake I hope the thermostat is bad.