Regular running my SS is usually around 200, however my cooling fans are currently inoperative and if I forget to turn the motor off at a long light it can hit 250... :-(

 

I'm glad I found this forum AND this thread about temp issues. I just replaced the thermostat in my 2006 HHR after having the temp gauge stay cold and the digital go "----". My worry was how fast this little engine heats up and I'm seeing it vary between 185 and 197. Does the type of oil you run in it make a difference in operating temperature? It has Castrol Edge 5w-30 synthetic in it. Is that particular oil good for the 2.4L engine?

My other question is the temp sensor. What would be the closest on true engine temp? Napa, Borg Warner, AcDelco? Or is this moot?

 

Your thermostat is stuck open that’s why your gauge shows _ _ _ _ , you will need to order up an AC Delco 131-158 thermostat,

RockAuto

don’t go cheap on an aftermarket thermostat as they don’t seem compatible with your computer expectations

Here’s a discount code for our friends at RockAuto


https://www.chevyhhr.net/forums/supp...-2018-a-59821/

 

Oldblue - he replaced the thermostat already - hopefully with an AC DELCO one as you mentioned.

Squeaky duck - yes that temperature is just fine - don't worry about it, and don't overthink it. Same with the temperature sensor question.

Re: oil - you need to read your owners manual regarding the type of oil - it says 5-30W is what is recommended, so that is what you are using. The type of oil will not make any significant change in the temperature.

 

On cold weather days, you will find that little benefit to be exactly that.
My cabin is comfortably warm within the first 5 minutes of driving and I LOVE THAT!

 

That’s what I’m recommending, to Squeaky Duck. Also , to confirm, you did use Dexcool to refill the cooling system, didn’t you?

 

I believe that's what my mechanic used when the thermostat was replaced. so far it runs fine.

Now IF that is not the case, what problems will arise? I ask because I read here some HHR owners are using regular coolant with good results.

 

Cool, pun intended

 

A. green stuff has a 2 year life
B. DexCool has a 5 year life
C. green stuff is designed for iron
D. DexCool is designed for Aluminum alloys
E. green stuff is designed to fill small holes (like those found in modern engines)
F. DexCool will try to fill holes to atmosphere when it over heats (when and where it is needed)
G. the entire Ecotech engine is designed for the heat transfer characteristics of DexCool

Top of the head, there is more.

 

Well so far my HHR seems happy with the new thermostat. The temp gauge works fine, the AC works again, heater is hot enough to scare a snowman and now the remote start is working. I had to go on a 300 mile run (work) which gave my car a good test run, so all is good. The temp pretty much stays around 188 to 190, but I did see it climb to almost 200 when I was not moving at a looooong stop light and then the fan kicked in dropping it back down.

I'm glad this forum is here, otherwise I'd be throwing hard earned money at the problem.