If you mean you had a P0128 code then , that code shuts down you AC , cruise control and cooling fan runs longer.

https://www.obd-codes.com/p0128

 

I wonder if your coolant recovery tank level is getting higher and higher.

 

Burp procedure ,

https://www.chevyhhr.net/forums/how-...-system-60614/

 

I don't remember which code it was but I erased it when I got home to see if the temp reading would come back. I did 3 tests without any stored codes and the fan behaved the same way all 3 times. The car was parked while idling and warmed up that way so it could get up to temp even with open tstat.

 

I didn't check. It had a decent amount in it when I did take a peak. I had the cap off and didn't see any bubbles coming up.

 

The computer deals with overheating by turning cylinders on and off and flashing "dummy" lights at the "driver". Not by playing with the idle. The reason for high idle after cleaning the TB is the solenoid gets stuck in the wrong position because of solidified grease, replacing the TB should fix it.. The resetting computers thing is just BS. The tech was trying to say that there is a TSB for 2007 2.4L regarding replacing the injectors and programming for them. The tech was aware of something he just didn't bother to find out the particulars.

217F is "normal" if you are sitting still a lot. Are you someone that turns the recirc on? Or drives with the defroster on? I am skeptical about the fan not turning off, it will continue to run after shutdown if the temp is above 240F.

RJ is hinting at signs of blown head gasket.

 

Don, you're misunderstanding the issue. No injectors were replaced to fix the high idle. according to the dealer and other people on the net the HHR with the 2.4l engine was built with 2 different injectors from factory. Grey and another color (blue?). For the 2 injectors there are 2 softwares for the computer. I have grey injectors so they flashed the blue injector software on the computer and than back to the grey one to force the computer to clear all adaptations. The throttle body was not sticking and after the flashing the computer I have no more issues with the throttle body. It works as intended.
It might be a coincidence but after fixing the high idle issue the overheating started. But it appears like the engine is not running hot because the cooling system can't keep it cool but because when the car is stationary the cooling fan does not turn on when it used to. Could someone check with a 2.4l what temperature the cooling fan turns on at? I know for a fact that mine used to turn on at 208-210F before but it won't anymore until 217F and refuses to turn off after.

I get what RJ is suggesting but I've seen no signs of a head gasket failure. That being said I'm not ruling it out just yet either.

EDIT:
I reread you post about the fan. So after the engine reaches 217F the fan turns on and refuses to turn off regardless the engine temp. Right now I have a tstat installed that's stuck wide open and while the car is stationary the cooling fan can cool the engine down to 130F while the engine is still tuning and the fan would not turn off. If I turn the engine off the fan turns off. IF I start the engine again the fan is off until temp rises to 217F and the whole thing starts again. I do not use A/C, recirculation or defogger unless I have to. Haven't used A/C since last year, never used recirculation without A/C and defogger maybe twice this year.

 

Time for a compression and leak down test!

cooling fan comes on at 219 or when the AC is turned on

 

Not necessarily a head gasket. Any leak, pressure cap, pinhole in thermostat housing, etc. The rising pressure in the cooling system from normal operation pushes coolant into the recovery tank. But if there's a leak, the sealed cooling system is not sealed anymore, and therefore it's difficult to get the coolant back into the engine.

Theoretically, anyhow.

 

Don’t forget the cracked filler neck issue, I had in the BlackSwan a few months ago