I am new to the forum. We have an 09 Silver HHR LT1 with a 2.2 and it has 20K on it now. Question on the engine temp, it was reading 186 and the dealer replaced the thermostat and it nows reads 181 in normal highway driving. Apparently they think this is normal because of where the thermostat is located, but I did have the opportunity to drive a similar one the other day and it was running closer to 200. Does anybody have any thoughts on this?
Thanks!

 

Why was the thermostat replaced? Temp seems to be below normal now but also was before repairs.Not by much, but a little cooler is better than overheating.Someone else will jump in with more info.

 

186 is what I would call normal (typical for our 2.4L) - and 200 is not a problem either. 181 seems a bit low to me. Keep an eye out for the temp display to read "----" and the temp gauge to drop to the bottom - if it does that, it indicates that the engine is not coming up to operating temperature fast enough. And that generally is due to the thermostat jammed in an open condition.

As other poster asked: why was the original thermostat replaced?

 

I have a 2009 LS 2.2 and my temp ranges between 186 & 215 depending on traffic, speed, AC on, outside temps, etc. It is listed as a 180 degree stat but with variables it will change. It almost seems like they forgot to put the thermostat in or your fan is stuck on- 180 is definitely too low.

Or you are using this forum from a Polar Icecap...

By the way-Welcome to the site & enjoy your ride!

 

I thought they used 195 degree or higher thermostats on newer vehicles because higher temperatures help with lower emissions and keep build up off the oxygen sensors.

 

I seems ours is a 180 unit for the 2.2 & 2.4 (could be wrong but all the different parts sites list 180 as the OEM replacement. Even my wifes 05 Cobalt is 180. maybe its due to the cramped space in the engine compartment? They run close to 200 degrees anyway. Maybe a 195 would let the HHR run too hot.

 

I would agree that 180 is what is in the 2.2. Mine runs low 180's, unless in traffic or the weather is hot. Gets to the high 190's, then the fan kicks in and its back to the 180's. In really hot weather, 100+ degrees, with the AC running, at highway speeds it will run 200, to 215, then cool some as the car slows. Regardless, in three and a half years, it has never been a problem.

 

Driving to work this morning-27 mile away to Brooklyn-with cruise control set at 55-temp was (drum roll please) 180. BTW I got (according to DIC) 36.5 MPG on the trip...

 

I know this may be a dead post by now but when ever your temp guage is not reading correctly after a simple t-stat change it normal means that the tech didnt get all the air out all temp sensors need the water contacting the sensor completly to get a accurate reading if the block has air in it the sesor cannot operate correctly.
also the tech may have put the wrong temp t-stat in your ride. either way insist yhat the tech rechecks his work and make him fess up to what temprature t-stat that he put in. remeber that in a mechanics world time is money and the only thing on his-hers mind is finishing up and getting the next work order. they have mouths to feed at home also.sometimes this need for speed ends causes a good tech to be a lame parts hanger.

 

I checked my 2006 with a 2.4 on a trip today. On the open road at 75 mph it ran at 192, would drop to 190, sometimes 189 then back to 192. It was 60 degrees ambient. It has the original thermostat which I assume opens at 192 degrees.