Hi,

I had my radiator flushed (2008, 2LT HHR, 2.4 engine, 21,500 miles) in March of this year. Historically, for the year I have had the car the average operating temp has been about 187. Now, I don't know if it's hallucinations and flashbacks but my car seems to be running about 5 -8 degrees warmer now on average.
My question is: Could this be a symptom of the system not having been "burped" properly at the time of the flush or is it a product of my hallucinations and flashbacks? :)

 

It should be running at 185 , depending on which T-stat it has but that should be a 185 degree stat from the factory , did the flush shop change the T-stat??

 

Not sure if they changed the t-stat but I was charged $60.00 for the flush, $26.79 for a "coolant kit" and $20.60 for coolant..........

 

Sounds like they didn't touch the thermostat, there could be some air entrained in the system that needs to work its way out. HHR's have an unfortunate design characteristic which places the heater core at the "high point" of the cooling system.

Running at 193-198 in town wouldn't give me cause for concern, it should settle down with time and driving. If you're seeing higher than normal temps at highway speeds, have it checked out. 187-192 is about right for highway engine temps, and here in Carolina there are the odd super warm days when you'll see a spike up to 212-217 in heavy stop and go traffic.

The cooling fans are set to kick on at 217 regardless, and they'll automatically kick on when you turn on the A/C.

 

I've made an appointment with the dealer that did the flush for Thursday morning and made them aware of my suspicions (that there is air in the system NOT that I'm having hallucinations and flashbacks! lol). With the outside temps in the 90s now and going higher next week, I think it would be prudent to have them check it outt and they do free diagnostic work anyway so, we'll see what the come up with and I'll post back. Good to know it wasn't just in my brain!
Thanks Everyone!

 

843de:

I was seeing 194 - 199 at hwy speeds today for about 2 hours, once in a while it would drop to 190 then go back up but I was watching the gauge as well (it didn't move)

 

The t-stat in American models is 180 F. That means AT LEAST 180F. The fan controls the high end. On my car 192F is "normal".

I wonder what a "coolant kit" is?

IF a GM dealer did it they should have used the official machine that exchanges the coolant, no air involved.

 

I'll add two ideas/thoughts.......

As the ambient temperatures rise so will the operating temperatures.....slightly. Depending on driving speeds and environment, temperatures will continue to lower and raise. I commonly witness 195-205 on my 2LT as outside temperatures rise between 90-110.

Additionally, my car operates slightly higher at freeway speeds of 75 mph....usually about 200+. If I slow down to 65 mph the operating temp drops back to 195-197 after a bit. I've noticed this on MANY cross country trips on Interstates especially.

I've said this before and I'll mention it again......the cooling system is slightly undersize for the vehicle, whether it is the capacity of the radiator or the water pumps inability to move coolant fast enough. JMO.

But it is worth the effort to have the dealer recheck the system.

 

Thanks Guys, Everything you've said makes sense. I'm just going by what I experienced in the year prior to the flush. Now, since the flush, it's acting differently and that's my concern so the dealer that did the flush is going to check it on Thursday just to be on the safe side.

 

Gee Snoopy, if you're seeing 200+ at highway speeds, you may want to clean the radiator and condensor by flushing them from the engine side. You'll be surprised by the amount of dirt and suicidal insects trapped in the fins choking off airflow.

Mine all get an annual "external backflush" and invariably, they disgorge a good amount of dirt and bug juice "gack" onto the driveway.