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.

[GriffGirl]

It totally sounds like your thermostat is sticking. The reason it's cooling when you hit 40 or so is because you've got better air flow and that's helping to cool things down some. If that doesn't work, try the radiator cap next; if it doesn't hold pressure, it'll totally overheat on you too.

I know this SUCKS in LA traffic/heat, but if you get stuck overheating, blast your heat, it'll help some with the overheating. Better to be really uncomfortable for a few minutes than risk blowing a head gasket. Also, keep an eye on that water pump - it's possible (not likely though) that it wasn't seated/sealed properly when it was replaced. It could be leaking some but evaporating from the heat before you ever see it drip. Your best bet in this situation if the cap and thermostat replacement doesn't help is to take the car back to where you had the work done and tell them about your problem and what you did to try to fix it. I had this exact problem with my 4Runner when I had the water pump replaced, and it turned out that it wasn't sealed properly and they had to open it all back up again (at their expense, of course)