2.4L possibly overheating?
 

Hello all, I searched the forums and couldn't really find if someone was having a similar issue. Ever since I bought this car last summer, the temperature would be just a hair above the center point. Over the winter, it's creeped up a little bit more than it was this summer. Occasionally it will get up to about where I drew a red mark on the picture. I changed and bled the coolant and it seemed to be okay for about 2 days and went right back to where it was.

When I turn on the heat the temperature goes down to normal and everything is okay. The heat seems really HOT though. I checked for the common symptoms of a bad head gasket (milky oil, smoke from tailpipe, loss of coolant) but haven't seen anything to make me concerned with that being the problem. I also checked to see if the fans came on, they did. I noticed the car runs pretty much at the half-way mark when I am driving on the interstate. My next guess is maybe the thermostat is stuck closed, could that be the issue? I let my car idle till it got up to temperature and checked the surge tank and there was no movement of coolant whatsoever.

To recap:
-Temperature above halfway and sometimes directly in between the 1/2 to 3/4 mark
-Seems to go to halfway mark when driving on the interstate and when heat is cranked up
-Heat is SUPER hot
-No movement of coolant in surge tank at operating temperature

If it is a stuck thermostat, what's the easiest way to get to it? Google and The Haynes Manual isn't too helpful on saying what to do.
I'm still new to all of this and am eager to learn the ropes. Thanks in advance for the help!

I have to admit, my 3.4L does that too and I consider it being nomal.
As long as the car heats up fast and stays there while stop and go city traffic your good.

Did you clean your cooling system? That is getting a good portion of the scale / limescale out? As this would hinder the radiator a lot, and would produce hot conditions if there wasn't enough airflow (e.g. city driving)

I cleaned it out as best as I could. The petrooster on my radiator was broken, and I couldn't fully drain it. ( and the lower hose is on so tight to get it off, I'd just have to cut it off and put a new one on, but I didn't have the time.) so I ran some radiator cleaning fluid through it and flushed it out by sticking the hose into one of the inlet hoses from the reservoir to the radiator and flushed it through the reservoir then filled it with distilled water and Dexcool.

Thanks for the help! I noticed other people were having a similar problem, but no one could figure out what was causing it.

I cleaned my out as good as I could - had heat issues in city and stop&go traffic.
Since then the needle behaves like yours, but the car takes about 10 min longer to get to temp in the winter than the years before.
So yeah, cleaning and getting the scale out improves on the heating issue.

If I were you, I'd keep an eye on it, and see if it gets worse this year especially under hard circumstances (hot, humid, slow traffic).
If yes, try to clean and de-scale your cooling system.
For know, you could pressure test your system and see if there might be an issue.
Weren't there reports of hair-cracks in the coolant reservoir?

It's been behaving weird. For over the past month it's been above the halfway mark, but today it was almost 70 out and after about 10 minutes of driving, went down to the halfway mark and even a hair below it. I wonder if the cold Ohio weather has anything to do with it running kind of hot. In the summer I rarely ever saw it go above the halfway mark...

The only way to know for sure is take a reading yourself.
Either way send the correct resistance through the cables, to see if the instrument shows correct.
or measure the sensor if you know exactly what temp he should be reading.

Thanks!