donbrew

The original question is moot, since the correct t-stat is 180F already. So, if you have a 190F in it you should replace it with the correct (180F) t-stat.

The answer to the OP is: yes, everybody has, since that's what came from the factory.

We have had reports of parts books listing 190F for the HHR, but those instances are incorrect.

aradmahogany

I still have a new one sitting in my garage waiting for Gregg's original t stat to kick the bucket. So far still working correctly! PN 131-158!! I'm quite sure the op has the correct and properly functioning t stat he just refuses to believe it! Running between 180 and 217 is a ok

gds1998

the main reason I posted the question was that I was thinking that my 09 HHR SS had a 190 t-stat as once warmed up it runs from 190-196, and stays fairly stable moving up and dn a bit as it opens and closes, but my 06 Cobalt SS gets to 181-183. and in the winter struggles to even get to 180 at times. if it is -10, -15 i have to drive 20+ miles before it warms up to full temp. so when comparing the 2 it seemed that perhaps the HHR had a 195 t-stat. from what I am being told however is that stock is 180, but wondering if the prev. owner my have gone to a 195 to get more heat in the cabin during the winter and also the cabin is bigger than a Cobalt...thanks to all for their inputs, changing out the t-stat looks like a SOB to change out just to verify if it is correct.

whopper

Have you considered that if the design of the thermostat in the Cobalt is like the one in the hhr, it may be experiencing the same failure of the thermostat that the hhrs see?

If that rubber gasket on the internal valve fails it jams it.open so it takes a long time to warm up, and often will run at lower temps.

gds1998

that sounds entirely possible, I have never had it out to check...better stuck open than closed!