Ill check the level in the tank after a warm/cold cycle and see if it changes. What a relief to hear that you cannot see flow also. I heard a squeak from the belt area upon start up twice, very short lived like 1-2 seconds. Thought it might be cold or the little bit of coolant I spilled causing the belt to slip. I am not a mechanic but I have been working on my vehicles, and repairing motorcycles most of my life (I'm 34) So I do not have too much experience with the little things many people of this forum are great at spotting. I can do easy to moderate repairs, know how to rebuild an engine though I have never taken a modern car apart completely (1965-75 GM V8s in high school etc.) I say this cause it "feels" like the coolant is not flowing through the system. I would think without my fan, driving alone in sub-freezing temps would keep the engine cool if the water was flowing through the radiator. The fan comes on at like 230F but makes no difference. It is almost like the heater is the only active cooling system in the car right now. I worry about driving it because if I'm able to manage the heat with the heater and the coolant is not actively flowing through the system, heater included, (Is that even possible?) (bad pump?) How hot is my block actually getting? Scary thought and I can about kiss my head gasket, or worse, goodbye soon. I think my next step is to take your advice and check for exhaust gas in the radiator. There isn't a "noticeable" leak in coolant yet but that doesn't mean I haven't blown the head gasket. We were also like -16 degrees F here the week before the fan kicked on killing my radiator. Thanks again. Once this is solved, I hope this thread helps someone.

 

Temperature test:

So, I decided to do a little test this morning on the way to work. The outside temp was 32 degrees.
Started the ride to work. Waited till the car hit full operating temp of 187-189. This is the normal temp for my car.
I was on a long 14 mile stretch of road with a constant 55 mph speed.
Now. I turn on the heater full blast. Within a half mile the temp goes up to 194 and stays there. ???
I go a couple more miles and turn the heater off. Within a half mile, the temp is back to the normal 187-189.
I repeat this scenario 2 times with the same results.

What do I learn from this? The heck if I know.

Point being. I'm at a loss for words on questgraves situation. I can't quite figure out why his cools down with the heater on but mine heats up just a little.

Oh well. Thought you folks might get a kick out of my little test.

 

I thank you for that confirmation of a little test I did last night with both my HHR and my Sunfire GT, with very similar results.
the only thing I can think of is the t-stat is not opening there by holding the coolant from flowing which would elevate the temp and when the heater fan is on, this would cool the coolant somewhat.
My thoughts are back to I know it's a new stat, but I would replace it with a GM part, re-burp the system with the right front corner higher than the rest of the cooling system, when you fill it up turn the heater on full heat face and footwell setting.

I looked at a Stant and Gates replacement t-stat's had the rubber ring, like the original t-stat , the GM / AC Delco redesigned t-stat did not

 

One more thing to check. Are the hoses collapsed in the morning before starting the car? (sign of exhaust gas in coolant).

I noticed today ambient temp around 11F, 500 miles drive with heat on high. a. heater temp went cold to hot cyclically. b. the coolant temp swung from 182F to 192F frequently.

I guess my T-stat is working.

The fan should come on around 220F, not 230F. 230F is getting into "limp home" territory.

 

One thing to think about...so you replaced your thermostat/radiator..then you topped off the coolant in the reservoir...then you "burped" the system...did you check to see if the coolant level is still high enough??? If you had a lot of air in the system, then you may have to add coolant to that reservoir more than once, because as you burp it, the air get replaced by coolant...I might not be right...but I read this thread like 4 times and tried to picture everything that the car would have done...and this is what I thought of...So recheck the coolant level

 

Thanks for all your input guys here is an update. Badassbowtie I continually check the fluid level to make sure there are no leaks or hopefully more air has gotten out of the system. I installed a backflushing "T" in the heater hose in the hopes to help get air out. It is nice to be able to backflush easy but no change in cooling. After watching all the "Eric the car guy" videos and tips on overheating, which I find awesome btw. http://www.ericthecarguy.com/faq/wha...s?limitstart=0
I ordered a funnel like he uses to get air out. On Amazon it has a ton of great ratings and good write ups on it's use to remove air. I didn't make it that far guys We are under a sever cold warning again -10 degrees F (note it was -16 degrees the day my car got hot enough for the fan to chew the radiator in the first place otherwise much like the test above my car normally stayed around 190) Sooo...today on my way home from work my heater never blew hot air...therefore no cooling and my car is parked 15 miles away ATM at a 24hr Walmart. The fluid level is fine. The fan works. When I open the "t" and rad cap, coolant should start to flow from the "t" from gravitational pressure but tonight it is not. oh yes you are correct my fan came on about 220 and stayed on untill about 190...wierd

 

I got one more stab at this...

so get the car warmed up ( as best as you can) and try to follow the coolant path...once its up to temp and the thermostat opens, all the hoses in line should warm up. considering how cold it is, you might be able to spot where the hot coolant isn't going, by carefully touching or grabbing the hoses.

Its hard to explain but the two radiator hoses (in and out) can tell you alot if they are warm or cold...

good luck to ya

 

Hmm. Got me thinking on this again badassbowtie. I had a overheating problem with my Dodge truck one time. After changing the thermostat and the waterpump and temp sending unit with no fix, I did a "feel" test like you suggested to questgraves.
On mine, I found the outer ends(tanks) on the radiator to be hot. The inner parts of the radiator were cold. Bingo! I had a plugged up radiator. Now, I bought this truck new and had flushed and changed the antifreeze at 30k and 60k miles. The truck had 72k miles on it when the overheating started. Changed out the radiator and it's been fine ever since. 167k miles and still good.

I know questgraves has a new radiator, but there could be a chance it's just not letting the coolant circulate.
Do as badassbowtie said and try the "feel" test. Check all the hoses and the radiator.

 

unless he got a bad thermostat out of the box??? I mean there isnt much else...the water pump blades can wear out over time..but they cant work before his incident and then not work after, right???

 

Well guys here goes... Turns out I did a really bone headed thing and somehow forgot to remove the cap from the lower radiator hose hole. When your done laughing please accept my apologies for eating your time. Thank you all for the help:)