Need help, I have a 2008 hhr ss, I have owed this car for about 2 months now, I am having overheating issues, with coolent disappearing. Spent 1000 dollars at the dealership and what was fixed did nothing for the overheating, did pressure test not sure what to do now, it also when it's cold in the morning starts rough until the vacuum comes down, don't really want to take it back to the dealer unless I have to any help would be appreciated. Thanks

 

this may sound stupid, but did you check the radiator cap? there are 2 rubber rings if they are flush with the metal, then you need a new one..i took mine to the dealership 3 times until they actually checked the cap...stuff happens.

 

Unless you tell us what was done by the dealer, it's hard to even attempt a guess.
Did a pressure test...and what were the results ?

You really should add in some details if you're asking for help.
Is it overheating when full of coolant ? Or overheating only after losing enough coolant.
If the coolant is disappearing and not showing a visible leak, it's most likely burning it through a cylinder. Possible head gasket, cracked head or block.

Some 2008's 2.0 lt Ecotecs had a production issue with block castings which resulted in some blocks cracking. Try a Google search for block "porosity" in the Ecotec line.

 

X2 to George's comments, we need more details mike even ones that may sound stupid.

There isn't much an HHR can have wrong with it that we haven't seen, but the devil is in the details, without them...we're shooting in the dark.

 

What temp does it get to and how fast, could be the rad cap not holding pressure .
How much coolant is lost ?
Do you see coolant under the SS?
Where drivers side? Passengers side? Tail pipe?
Could be the thermostat sticking closed!
Send your vin info in a PM to customer service they can tell if the block is in the group with issues and if the SS has been serviced for the porosity issues, if done under warranty

 

By "Dealer" do you mean a GM service department or the lot you bought the car from?

I know for a fact that if you buy a used car from a GM dealer, when you take it back for repairs they do NOT necessarily take it to the GM Service Dept. The used car operation is generally a different company.

 

Good point! Don

 

Only a few places for coolant to go; out the exhaust, into the crank case or on the ground.

I had the plug on the t-stat housing spring a tiny leak.

 

I bought the car at an average used dealership and had all the service done at a GM service center, had a full tune up with plugs and oil change, along with all fluids flushed and filled, t-stat changed, also a pressure test that they said had no leakes. The temp rises to upwords of 230 to 250 until I add more dex cool, about a little under a liter, run perfect for a week and then temp starts to rise. The car shows no visible leak. I love this car except for these problems, Thanks for the help.

 

Could be a bad t stat could be an air bubble in the system, if it was ok before the GM shop worked on it then take it back to them, take your invoice and work order with you!