I start driving to work and then the A/C stops cooling. I then notice on the DIC that when I scroll to see coolant temp, it shows ---F. Also the analog temp, the needle is laying all the way down, as if the key is not turned on. Do all THREE of these point to a thermostat?

 

Yes, AC Delco 131-158, 50/50 Dexcool and burp the coolant

 

How much dex-cool will run down the driveway if I just remove the thermostat housing?

 

I just replaced mine, seems like it was about a pint, maybe a little more.

 

I just did that also, it took almost a quart .

 

Mine didn't leave a mark.

 

So I just got off work. Started the HHR and immediately it read —-F. Is this normal? I thought it would read a temp for a minute or two, then revert to —-F. The engine light came on as I was driving home. It was raining hard today and I ran thru a lot of water, just hoping the water did not damage anything. I’ll change the thermostat in the morning.

 

The code is most likely P0128 . Before you change the thermostat, disconnect the negative battery terminal. You don’t need to be touching the power supply to the fuse box.

 

AND, the reminder that DexCool should be changed after 5 years.
"You can pay me now, or pay me later"

 

The code was P0128. The A/C did not work. The analog temp gauge read 0. The digital temp gauge read —-F . The engine light eventually came on after 20-25 minutes of driving it. The car would no longer remote start. The culprit was a bad thermostat, as you suggested. I parked the car on an incline, with nose pointing down, lost maybe half quart dex-cool when I opened thermostat housing. I found that two 12” extensions and a 10mm socket works perfect. No need for the wobbley socket or universal. Thanks.

I have owned 5 HHR’s and have absolutely loved them. This maroon HHR is my work car, it gets abused, driven every day, parked in the sun all day. I have 5 years left and I can retire and move to the beach. The plan was, in 5 years, to sell the HHR and buy a golf cart to ride up and down the beach and through this small community. I am now thinking about just removing the doors and lift gate and make him into a hoopty, instead of the golf cart. What do ya’ll think?