Thanks to all for the great suggestions! I decided to have a local mechanic replace the t-stat for me @ $95 I though that was reasonable. Now I just have to wait till it's done and see that it works properly!

 

See if he has the equipment to "pull a vacuum" on the cooling system, that drastically reduces the chances of air getting trapped.

Once the job is done, listen carefully for any "gurgling or percolating" sounds emanating from the passenger side of the dashboard, that means there's air trapped in the heater core.

If you do get the gurgling/percolating noises, keep an eye on the coolant level as the system burps itself, or go back and have a vacuum pulled on the system.

 

And did he install the correct GM AC Delco stat? Other brands can cause havoc with not getting up to temp in the time frame the ECM is looking for!

 

All is well with my HHR. Delco t-stat installed, system filled with dexcool, been 'burped', codes cleared, AC working just fine.

Thanks to all for the suggestions. This is a great forum

 

Your welcome, we aim to please! Great to here your HHR is running like a top!

 

A clamp had rusted off my lower rad hose this summer. I replaced the Clamp, changed out the t-stat and started bleeding the air out. It got up to temp, bubbled then seemed to be free of air.
A couple of months later, the system is full, the car heats up normally and kick out lots of heat but the reading on the display has blank numbers for coolant temp.
The wires and male and female connecter ends are free of currosion. So I put the front end on ramps. It pushed out more air bubbles and the reading came back. If not, I would take resistance readings and replace any deffective sensor. Fyi; A 400KM trip this past wknd got 665 Kms with dirrectional all season tires. So the fuel range is on par it seems. I don't normaly see 700 Kms with my 2.4L, 2LT, cold air intake, 5 speed and cross racks removed from the roof rack.

 

Thanks for confirming the front bumper higher than the rear gets the air out!!
Thankfully my driveway is 8 inches higher at the house then the road! Instant burping slope!!

 

Hi all! Back in September I posted about the temp gauge not working, replies said to have t-stat replaced, I did, all was well till a week ago. It’s been warm here in socal so I turned on the AC and no cold air. Then I noticed that the temp gauge not working again. I finally got and OBDII reader because the auto stores around here no longer will read/clear your codes.

There were two codes ( $7E8 engine) and ($7EA) neither of which can I find a listing of what these are. So I deleted these codes and the gauge was working again as was the AC. Yippie.

But wait, after a few miles of driving the gauge quit working again. I pulled over and checked the codes again and the same ones showed up, so I cleared them and all is good. Drive a few more miles and the same thing, no gauge, no AC.

Now I am frustrated and need help (please)

Thanks,
Jerry in socal

 

H'mmm, I typed "$7e8" into the search box and found this : https://www.chevyhhr.net/forums/prob...e-codes-41037/

Seems to mean you have a cracked flex pipe. And an Autel OBDii reader.

 

oh duh, I never thought to search for that code here, thanks for the heads up on that. If there is a cracked flex pipe wouldn't I hear some noise? The engine runs as quiet as ever.

As far as the brand of my scanner, which I got on E-bay is:
Konnwei model KW808