Time to operating temp (180 on dic)
 

Can those of you living in colder climates tell me about how long your the takes to reach operating temp or around180 on the dic specifically when it is cold outside? Also, how soon do you wait to turn on the heat of at all? This morning my the took about 10 minutes to read 181 on the dic which sounds a bit long to me . it was 54 degrees Fahrenheit outside.....Coldest the the has seen in a year lol. Once it reached180 it never dried below that even with the heat on.

Don't worry about the heater, the core is always "hot". The only difference would be the fan, and that is a fairly small percentage of cooling.

IIRC, in the really cold weather mine would be 180F in about 5-10 minutes. If you don't get a P0128 it's warming up quick enough.

I was just sitting in the parking lot at checkers waiting for my food when out of experimental curiosity I wanted to see if the car was capable of getting cooler that 180......well it actually cooled down to 178 until I was surprised and turned the heat off. I had it at full heat and full blast. Made me think maybe my thermostat is starting to go? Should the car stay above 180 once it reaches180?

I doubt that 180 is a line in the sand.

Wouldn't it be possible that there could be a slight delay on the down temp side when the thermostat senses 180 and has to turn around to the upside and the water temp could reach 178 for a quick reading ?

I feel that most thermostats can have a slight difference but not enough to cause any problems unless they are actually defective.

I have owned 9 - 2010 and 2011 HHR's and I have monitored 6 of them on a "Park and Idle" in neutral test to see what happens on the DIC.
The results showed that they each had a life of their own and they all had close to the same mileage .. 20,000 miles

I can tell you that where I live 54 is not considered cold, but I would guess that it is close to a 10 or more minute run time at idle to get to approx. 180 starting at 50 outside. If you need it sooner put the pedal to the metal.
I can start the car in the garage at about 50 degrees , back out and head for the local coffee shop which is 1 mile, and even with driving a mile my temp is not to 180 yet.
I know because I turn on the heat as soon as I pull into the drive in to start heating my cup. I have checked the temps many times so I have a pretty good feel what's happening. I have done this with each one of my HHR's and they are all roughly about the same.
1 was a 2.2L and all the others where 2.4L
The other contributing factors of course are the fans and their sensors and cycles.

You don't mention how many miles or the model year but is your coolant needing changing?
A good time to do the thermostat and other related parts and in case you don't already know... use AC Delco only...

SF

When it's below freezing here, I leave after idling for about 20 seconds and it takes about 4 minutes to get to 140, which is when I turn on the heater so I feel hot air. Then it goes up slower to 180 degrees, which takes an additional 6 minutes or so for a total of 10 minutes. I am driving on 55mph roads for all 10 minutes of warmup.

And yes, you can pull the temp a little below 180 if you run the heater while idling.

Steve

Looks like another case of my overthinking anxious mind. This AM when I started my commute it was 45 degrees F out, took a bit under 10 minutes to get to 180 driving at 50+ MPH. I think that is normal according what you all have posted. I am still running the ortiginal T-Stat (at least original to me since I took ownership at 135K miles) at 190K miles. I had my coolant serviced a little over a year ago.

Yeah, sounds like you may have "overthunk" it. :lol:

Besides that, seems the Tampa area is experiencing some rare cool weather for this time of year. Will probably be back to the 70's/90's before you know it.

Shivering in your house when it is 72 degrees.... Florida resident problems XD

Here is another thing to consider when you are checking "outside temps" on the DIC.

Most all of the HHR's I have owned have had faulty temps displayed intermittently.
Some more then others.

The sensor goes bad early on. It can be off in both directions.

GM must have produced a ton of short lived sensors and it seems nobody is noticing it or complaining.

My current driver is constantly picking a temperature and then sticking there.

Has anybody seen a TSB or recall on this issue? ... I haven't.

I would complain but I forget every time I go in for service.

SF

Hm.. I think mine is still fairly accurate. Seems to fluctuates as it should.... Engine heats up while accelerating up hill and rapidly cools coasting downhill. Also fluctuates in stop and go. Maybe I am lucky?