I just bought a 2001 LS from a woman who claimed it had a blown headgasket. When I first looked at the car I topped off the coolant and test drove it. I bought it and drove it for three weeks before the temp came up on me in the Krystal's drive-thru. I pulled over, ate my food, drove home and topped it off again. Haven't had it happen again yet.

Every time I open the radiator cap it releases some wicked pressure. The lady replaced the radiator, cap, hoses and thermostat before selling it.

Dosen't smoke and no coolant in the oil, but there is some coolant loss.
Do you think I have an extremely slow leak in the headgasket?

 

No smoke, no coolant in oil, doesn't sound like a blow head gasket, guess it could be a very small leak.

Any sign of coolant leaking around the head?

I would have a very close look at the rad, where core is "crimped" to the top and bottom caps, that's where both my original and the replacement OEM rads leaked, just like yours a slow loss of coolant over a 2-4 week period, depending on how much car was driven have since replaced the rad with a custom triple core, no problems since then, [11 years].

I found both leaks by cleaning the rad very well, used compressed air to dry it off then checking it constantly after driving or running the engine, took 3 days the first time, but finally noticed a wet spot just behind the rad cap, second time it took 3 weeks as leak was at the bottom cap.
Have a few friends with G2s and G3s that had the same problem.94

 

I'll have to check that out.