yea mine NEVER works i'm sure its cause my job because i stop from house to house and leave the car on so i dont burn out the starter but w/e temp it is when i leave the house in the morning is the temp it reads all day even though i drive about 50mph for 15mins..

 

the outside temp guage is horrid in this car. i have no idea where the sensor is but on mine it will usually read about 10* lower

 

If you want to know.........

https://www.chevyhhr.net/forums/general-hhr-4/where-temp-sensor-13161/

 

My old 07 and current 07 (wifes) both always read about 4 degrees high, but the 08 seems to be much better!

I have a professional Davis weather station, and that is what I compare them too, and I trust the Davis.

 

I still think the way the gauge works is STUPID!! Yesterday, I "ran errands" all over town--and the gauge read 50* all day (morning temp)... It got to the point that I would "try" to make the distance between stop lights 5 minutes!!

But that did not work out... It seems the average time was about 3 minutes between "stops"..

So, just to see, I went onto the Freeway and used my clock as a "starting time"... YEP--after exactly 5 minutes of non-stop driving I watched the Temp Gauge quickly "scroll" up to 68*....

At least I felt better knowing the gauge-timer-speed sensor is working OK...

 

Ive been crabbing about this for 3 years, since my buddy bought his first GMC Acadia. I t does the same thing. my 07 HHR dows it as well. I had a 95 Dodge Ram that seemed to be accurate immediately and always, Grrrrrrr

 

I complained about mine, the dealer said they all work that way. When its cool outside it works great, but in the summer when its significantly hotter outside then in the garage, it takes aobut 10 to fifteen minutes of freeway driving before it reads accurately. Can't be in stop and go driving. I have other cars, that work far better than this, its dissapointing at best, and there should be a way to program aound this, say set it for 18mph or faster for 2 minutes instead of fifteen. That to me would be far more realistic.

 

My 2008 HHR LT has been back to the dealership 3x for this same issue.

They still dont have it right.

My 2000 Silverado is always within 2 degree's of the real temperature.

Its that they cant get it right on the 2008.

 

So almost the whole drive from school today it read that it was 40 outside, and believe me...it was much warmer than that. About 10 miles from home (half way) it finally shot up to 66. Now, I had been driving country roads anywhere from 45-60 and it never did change until I had been driving for about 20 minutes or so....

Who knows......

 

This is my first car with the temp in the DIC. All of the others were in the mirror or heater controls (GTP). On the GTP, the engine heat wouldn't affect the outside temps. On my Silverado, it would. GM apparently got enough complaints to decide to try and out-smart the reading and in the process confused everyone.

When I saw my SS do this, my first thought was the DIC was bad, but after reading the explanation, I get it. If the outside temp is higher than the last reading when you shut it off, they assume engine heat is going to affect the probe and wait to get a new reading. Unfortunately they wait far too long for my tastes.

So you have a choice( not really):

1. The outside temp reads a bazillon degrees when stopped or after restarting on a hot engine and then drops to the correct temp once you get moving, or;

2. The gauge is stuck at a lower temp until the DIC decides it's safe to update it with the new higher temperature.

I dunno, I knew what was happening with the heat soak so I just waited a minute or so for it to go back down to the true ambient temp. Now I get to wait 15 minutes for it to rise to the real outside temp.