2011 Chevrolet Aveo Overheating & Pushing Coolant

[eaweld]

Have a 2011 Chevrolet Aveo LT, actually have 19 of these cars we use as delivery. So very much acquainted with the craziness of some normal issues. This one has me stumped though, 2011 with 41K on the clock, the car will once a week, peg the temperature gauge, and push all the coolant out of the resevoir. So far I have replaced the radiator, radiator cap, thermostat... Cooling fans are operational during overheat issue, and coolant is flowing. I have performed a block test with the test fluid all of which show negative. Was able to catch the car while doing its overheating spell and performed block test at that point. Fluid never changed colors... The only thing it really leads me to believe is combustion gases are still getting into the coolant either thru bad head gasket or an issue with head or block. Anyone had this issue before?

[Pickles]

Sounds like my issue, other than the temp gauge going up...
I just ordered a new radiator cap, I'm gonna get the head gasket tested if that doesn't work. Strange though, no bubbles in coolant, no coolant in oil or vice versa either. Still doing it after I replaced the thermostat as well

[eaweld]

And I have had another aveo with an expansion cap issue, so learned to do that issue first. This one I have gone thru everything including the $100 thermostat on the newer cars since it is computer controlled. Performed the block test with the test fluid still negative. But it would really need to be combustion gases or compression getting into the coolant to push out of tank. Spark plugs are fine, nothing making it internally into combustion, but it definately pressurizes tank and boils it

[Pickles]

I wish I did that first... $130 on the tstat

[Chevy Customer Svc]

Hi eaweld

Please let me know if you would like to take your Aveo to the dealer. I can start a Service Request for you, check your VIN for any updates and also locate the nearest dealership if that would be helpful. Just send me a private message and I will help you.

Jackie
Chevrolet Customer Care

[whokadog]

The exact same thing happened yesterday to my 2011 Aveo LT did you find a solution? was it a thermostat or Cap issue?

[Pooh Man]

I would do both, these coolant systems aren't very good...had to replace the overflow tank cus when I turned it off while hot the coolant would piss out the bottom, I guess it had a slight failure in the plastic weld

[petrified.rabbit]

this is one of those things that you can't really diagnose over the internet, the system losing coolant like this could be from a pressure leak, or added pressure (head gasket). While I have not heard of common head gasket issues on these cars yet. Even a pin hole leak that takes the pressure from the system will allow it to boil over and out.

pressure raises the temperature it takes for the coolant to boil (boiling point)) so if you lower the pressure with a leak or open system it will lose coolant at a lower temperature.

[Susie]

My 2011 Chevy Aveo has had overheating problems 3 times in last year. 11 mo ago, overheated. New thermostat put in. 4 mo later, thermostat failed. Was replaced. Today, overheated. It may have now done serious damage. I again had to be towed. Hundreds of dollars down the drain. I need to speak w someone ne w Chevy a sap. There appears to be a serious note Susie's w Aveos and overheating. Is it perhaps time for a recall on 2006, 2008, and 2011 Chevy Aveos???!!!!!!!! This is RIDICULOUS!! I had no idea thousands of us are having this issue!!! Susie, Iowa. Susan.grace74@outlook.com

[rrail2678]

Just had the exact same issue, Blew the intake bypass hose, replaced and the car continued to boil over after just a few miles, changed the thermostat, expansion cap and still boil over after a few miles. finally took the car in. Mechanic thought head gasket at first then found a small but visible crack in the block between the #1 and #2 cylinder. The shop states this is a common issue with these yet I cannot find anything on the web confirming this, consequently there are many post with this overheating issue being described in this forum with few to no quick solutions.