Turns out, that's exactly what it was. I was dreading the headgasket, but I checked my cooling system one more time just to double check. Turns out, the rad was almost empty and when I removed the rad cap after it cooled down a bit, the main rad hoses went limp... so I refilled her, and she's been fine. Thanks for the help guys. This means I can beat the ---- outa her even more

*The water it was spitting was just vapor as it is getting cool here now*

 

Ive also doen this today. I ran the car with the rad cap off and filled up with water while watching little bubbles come out. After about 1 min of slowly pouring, the bubbles finnaly stopped, even after the engine was revved.
It go past 1/2, but i still think the hot air from the turbo makes the cooling weaker.
After idling for a bit the temp stays to 1/2 now, and even if i roll down a hill with it idling in nuetral the temp guage instantly goes down.
I guess the solution is to install a stronger rad fan.

 

Mine was doing the same thing... for four months. Perfect compression, (not the HG), filling the resiviour (sp). Over and over it would overheat, but usually the heater would fix it (turning it on)...

Bled the system, changed the coolant, same thing... Kept happening. Every time it would overheat the fan would be on but blowing cold air... and when it wasn't overheating everything would seem normal.

I did... nothing. It fixed itself. I swear to god. It's been 10k miles... and perfectly normal again. I don't have an answer. It was overheating last winter, and when summer rolled around, it went back to normal. Still fine today.

Go figure.

Matt

 

CHECK the coolant level! Go to the back of the motor were the thermostate is there should be a release valve for air bubbles. I had the same probloms in my 97 LS ALL OF A SUDDEN. It kept on doing it for a week or so then stopped. Good compression no mixture in the oil or water.Just a simpe check if you haven't done it already

 

the problem was fixed. mine had the fan switch sensor fucked up and the fans would turn on at idle, but after the car warmed up the fan switch sensor wouldn't turn the fans on anymore. replaced the fss and overheating stoped.
also, radiator caps,fanswitch sensors, and thermostats come in different kinds. the new fan switch sensor i installed turns the fans on at 189degrees the old one at 191degrees-that's what it says on the fan switch sensors. also, i bought a radiator cap that vents at 13 lbs and the factory one vented at 16 lbs, if it starts to vent sooner it'll start to cool down sooner.