2009 HHR LS started overheating a bit. It will get around 212 degrees. Seems to be mainly when idling. Temps will drop to normal at freeway speeds. So thinking thermostat or waterpump. Are there any HHR specific tests to isolate the issue?

Robert

 

212 is not overheating.

 

Have you check to make sure the cooling fan is coming on? It should kick on a little North of 205. 212 is normal in warm weather when standing still with the a/c off. With the a/c on, the fan should run constantly.

 

Cooling fan doesn’t turn on until 217-219. If the AC compressor is on (ac, defrost, recir mode), then the fan will be on regardless of coolant temp.

 

Yeah, mine does just like that. Sure wished I could get it to come on at about 200-205….just seems to hot to me. Mine comes on at 213 ish

 

Not HHR specific. Before a cold start, remove the pressure cap from the coolant filler neck. Make sure the coolant level is full. If not, top it off, then burp the cooling system per the method Oldblue outlined in the how-to tutorial forum.

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

If it's not full, you need to find out why. The filler neck has been known to crack and crumble.

 

DexCool coolant needs to be replaced every 5 years. I had mine changed and it made a big difference.

 

Btw, my 212 degrees was just a estimate at the time. It went much higher. My temps are usually in the 190's. All these suggestions did remind me that two or three times I have seen my temperature gauge not reading anything. I thought maybe it was because of the cooler temps right now but it happened at least three times so maybe I just have a problem with the engine coolant temperature sensor?

 

If your temp goes to - - - F then you have a problem. Mine was due to the thermostat sticking open. this also shuts down the A/C from working. caused by temp not getting warm fast enough for the computer's liking. I know it doesn't make sense and you'd think it would be a temp sensor, but it isn't. replace the thermostat with a AC Delco unit or it will happen again too soon.

 

I wonder if you are not mentioning the CEL?