I had my car in to the local dealer on Monday (3 days ago) because it was using a little coolant (not a lot) and they could find no leak. They added the GM pellets and a dye and told me to come back if it was still using coolant. It's too soon right now to really tell if it's using much coolant, but now it seems to be running consistently on the hot side of normal. Now every time commuting to work or coming home, the cooling fan continues to run after I shut the car off. This used to only happen if it was hot outside or I was pushing the car a bit harder than normal. Now it happens all the time.

More specifics:

Outside temps have been 30-45 degrees during the last few days
My commute is ~23 miles, mostly highway.
Once warmed up and driving on flat highway (55-70MPH) the temp will run 210-216 constantly, usually 216 towards the end of the commute. In the past it wouldn't run this high except maybe when going up a long hill.
On the way home there is a bit of a hill and it hit 221F yesterday on the way up. It eventually dropped to 216F on the rest of the trip (flat highway)
Car has 59K miles on it (I've had it since 5K)

Is there any likelihood those pellets are restricting something? Since it isn't technically overheating, I am thinking the dealer may not want to do anything with it. The issue is it didn't do this before. I guess I can wait for it to get worse... powertrain warranty is good until early March. Does anyone else's SS run this hot normally?

 

Good Afternoon pitbull76!

I realize the information I’m about to post you may already know, but I thought it would worth while to post it anyway.

On page 5-24 of the 2008 Chevrolet HHR owner’s manual it reads:
“The cooling system in your vehicle is filled with DEX-COOLŽ engine coolant. This coolant is designed to remain in your vehicle for five years or 150,000 miles (240 000 km), whichever occurs first, if you add only DEX-COOLŽ extended life coolant.

The following explains your cooling system and how to add coolant when it is low. If you have a problem with engine overheating, see Engine Overheating on
page 5-26.

A 50/50 mixture of clean, drinkable water and DEX-COOLŽ coolant will:
• Give freezing protection down to −34°F (−37°C).
• Give boiling protection up to 265°F (129°C).
• Protect against rust and corrosion.
• Help keep the proper engine temperature.
• Let the warning lights and gages work as they should.

Notice: Using coolant other than DEX-COOLŽ may cause premature engine, heater core, or radiator corrosion. In addition, the engine coolant may require changing sooner, at the first maintenance service after each 30,000 miles (50 000 km) or 24 months, whichever occurs first. Any repairs would not be covered by your warranty. Always use DEX-COOLŽ (silicate-free) coolant in your vehicle.”

I was hoping to be able to find the normal range temperature the vehicle should be running at, but unfortunately I can’t. In the owner’s manual of my 2004 Chevrolet Tahoe, I read what the normal range was. This is very interesting that it wasn’t in this owner’s manual.

I hope things will get resolved soon.

Michelle, Chevrolet Customer Service

 

Sounds like it has that "air pocket" that the HHR cooling system can get. Maybe when the dealer topped it off, they didn't burp the system as they needed to.

 

Sorry. Missed the last part of your question.

Mine usually runs in the 185-190 range under normal driving.

 

Thanks for the response. What's weird is mine has never run that cool. In the past it was more like 205F once warmed up.

 

My 06 runs 196 +/- 5 degrees, even in the Florida summers. Maybe get to 215 when stopped in traffic. The dealer flushed the coolant at 50K miles and my local garage flushed it again around 100K non dex cool. I haven't seen any variations in the temperatures since that last flush 5000 miles ago.

 

My SS runs normally between 200-208 all year round. The warmest it has ever gotten to is 216.

 

[QUOTE=djr1973;683683]My SS runs normally between 200-208 all year round. The warmest it has ever gotten to is 216.

Same here.

 

If its "using" coolant, it could be a sign of an internal leak. Since they put dye in the coolant they can check to see if the engine is actually consuming it.

 

A leaking head gasket could allow engine compression into the water jacket and force out some coolant through the rad cap.
I am under the assumption that if you have an aluminum rad. Then it MUST be dex cool. Not the regular stuff.....correct me if I'm wrong on that.
Also if a thermostat fails, it could fail a little bit closed. I had a "guaranteed to fail open" thermostat fail closed and overheat my engine.......man was I mad.
anyway...just my thoughts.