Alright, I've been posting about this for awhile and thought I solved the problem when I found out that my P/S cooler failed and was mixing in the hot ps fluid in with the return side coolant. I had bypassed the cooler and thought everything was good. I no longer had as much of a problem with a overheat condition when I restart the car after 5 minutes of it being shut down. Before the gauge would jump into the 240+ zone, but now it just eeked a little over 210-220 before coming down.

Before I continue, I've read that only 98s have true temp gauges and that after that it just goes up to 210 with a 25* leeway + or -. However, I am the second owner of my car plus it was in an accident where my radiator was replaced (OEM) so it's possible that somewhere along the line the sensor was changed to a 98 one. I say this because when I drive to work on the freeway in the morning (55* out) it will stay at around 170-180 until I get off the freeway about 15 minutes later. It'll also stay quite a bit below normal 210, about 200 judging by the gauge when I baby it in the cold.

After normal driving it goes to right below 210. Now, later in the day when it's about 75+ out, it'll be at 210 and occasionally peek over to about 215-220 for about a half minute before the fans kick on and bring it down. Now, if I'm on the freeway at that time it'll be doing the same back and forth thing even though I'm in 6th at 1500 rpm. Once I down shifted to 4th and kept it at about 3500pm. The damn gauge kept slowly going up to about 24-260 until I finally upshifted. It was about 75* out. I've drained my coolant several times and haven't noticed any differance.

Now, could this be what 98 owners experianced that made GM switch to the dummy style system? I really have no idea if my temp sensor was changed, but it seems a lot more picky then what you guys say how it should be acting. Still, it bothers me that it went up to 240+ that one time. I'm planning on going road racing sometime soon and need to sort this out. I dont want to spend my $300 track day overheating in the parking lot. I'm going to drain it one more time and fully flush it with distilled and use water wetter to try to cool her down. Any other ideas? Sorry this is so long winded, there's just a lot of background stuff I had to put out there.



BTW: My air dam is fine and yes, I've done many searches about this on this site and ls1 tech to no avail. None of the other problems related to mine.

 

I believe water wetter would be a band aid, until you actually get the problem solved.
When you fill the coolant system, do you bleed it correctly?
If not, here is how to do it, start from #13. It is very critical this be done, or there will be air pockets in the system causing this.
http://www.installuniversity.com/ins...ostat_swap.htm
My car runs around 180* on a 90* day. I have a 160* thermostat and fans reprogrammed. I wonder if the last owner put a 160* thermostat and didn't reprogram the fans.

 

Yeah, I realized that the wetter wouldn't be fixing my problem, but I'm getting so frustrated with this. I installed the therm myself, following the instructions that came with it but my fan settings are still stock. I didn't do that process though that was on the site. I'm going to try that tommorow. Wouldn't an air buble situation though work out out itself? I mean, after a day or so of running it, the air bubble would be pushed out and you would notice that you needed to add more coolant. I check mine routinely and haven't noticed this. Thanks. I'll post again after i change the coolant ( YET AGAIN. I've bought about 5 gallons of dexcool so far becasue I have changed it so many times.) following those directions to see if that is it.

 

are you running the dexcool, 50/50 mix? I bought a 1 gallon pitcher ($1 store) to get mine 50/50.
You said you installed the thermo, I see in your sig it is a 160*. You really need to get the fans reprogammed. It helps out alot. Otherwise the fans do not come on till 210 and 220. Mine is set to come on at 180 and 190. I have the dummy gauge and it actually reads lower than it did with the stock thermo and fan setting.
As far as the bubble, depends on where in the engine it is at. I would think it would work itself out, but after owning a T-Bird SC, bleeding the system is very criticle.