ebritt

Hey Guys,
My temp gauge stops at 180 degrees, the info center works just fine. Is there more than one temp sensor in this vehicle? If so which one runs the gauge?

Thanks

unique_w

The temp sensor in located at the top right rear of the engine, it is basically a rheostat that varies in resistance based on the temp of the engine/coolant, it connects to the ECM, I believe my thermostat opens at about 180 degrees, thermostat's are available at higher and lower temp operation, but it is wise to adhere to what GM recommends.

macarchie

Sounds to me like the thermostat may be stuck open. Does it take longer to warm up than usual? If the thermostat never closes, then the engine may not fully get up to operating temperature.

davidjb

petty sure most of our cars cars run a 195 degree thermostat, yours might be stuck or somebody put a lower temp one in.

unique_w

CrazyCarKid states his runs anywhere from 182 to 191 degrees, ref: thread below.
The coolant thermostat opens at 180 degrees, per prior research. As davidjb stated yours could be stuck, if so, it may be covered under the drive train warranty.

https://www.chevyhhr.net/forums/show...t=temp+reading

Also -

https://www.chevyhhr.net/forums/problems-service-repairs-42/temp-guage-flat-coolant-temp-21362/

Smoke Wagon

usually if the T-Stat is stuck OPEN, the car will not "warm up" fast enough and you will get this:

https://www.chevyhhr.net/forums/showthread.php?t=21362


which means you can then do this:

https://www.chevyhhr.net/forums/how-tutorial-library-21/how-save-%24350-00-thermostat-replacement-2-4l-p0128-24493/

urbexHHR

Correct. I have never seen it past 191.... But mine does not take long to heat up at all.

ebritt

No, your misunderstanding......the temp gauge in the instrument cluster stops at what looks like about 180. But if you bring up the menu in the info center, the "coolant temp" shows the actual engine temp and the engine is running fine, anywhere from 189 to 217 when idling in traffic. Only the Gauge stops when it reaches the same point on the scale.
My question is...is this a 2 sensor system? Some of my other vehicles had 2 sensors. 1 went to the computer and one ran the gauge only. If only one sensor then my gauge is bad. And the question then is, can the gauge be replaced or the whole cluster?

mistermike

If the gauge doesn't agree with the data output from the ECM, it is bad. These things run off stepper motors which can bind up like any other mechanical device.

Snoopy

ebritt....

To answer one of your questions.....yes, I believe some earlier threads indicated the hhr HAS 2 SENSORS.

Also.....your car may NOT have a thermostat STUCK OPEN. Just one that will NOT CLOSE ALL THE WAY. Again, earlier threads discussed an issue with thermostats not closing all the way because of a material shreading that is used to coat the lip around the round thermostat head opening (thus causing improper closing). But your HHR sounds like it's running correctly.

The analog indicator has a poor relationship to actual temperature. I noticed this because I drive with the DIC constantly on the coolant temp. Sometimes, while experiencing 115 degree ambients and in "city traffic" I see 220-225 coolant temps. While climbing into the mountains I've witnessed 235 coolant temps. Either time, the analog barely moved (perhaps 1/16 to 1/8 inch)to indicate such a radical difference.