Hi everyone,


I own a 2011 Chevy Aveo, 50k miles.


5 months ago, while driving on the highway, the engine started to overheat and temperature gauge approached the maximum. I stopped at the closest garage, they found an antifreeze leak, changed the thermostat housing and radiator cap. Car worked fine for the next couple of months after that.


For the past few weeks, I've noticed a sweet smell when I turn on the heat. After a quick research on the Internet, I found that this could also be caused by an antifreeze leak. That being said, there is no sign of the engine overheating.


I brought my car to the garage I usually go to (not the same one mentioned before). They said they found a small leak and suggested we start from there before taking a look elsewhere. I've been going there for a few years and I trust them so I didn't really ask any questions. However, when I received the bill, I realized that they had actually changed the thermostat housing (which had been changed four months ago). I didn't notice this on the spot, only when I came back home on Friday evening.


And now, the smell is still there. It's not constant. If I let the heating to the first level, I'll smell it maybe for 30 seconds, than it's fine, and it comes back after. Also, the engine temperature gauge has been acting weird this weekend. It goes a little bit over the middle (which it doesn't normally do) and sometimes drops a bit, but mostly stays where it should be. Another bizarre thing is that yesterday morning, I started the car after a freezing night and the gauge went up near the middle in only a minute (but stopped there), while usually, it takes a lot more time.


With all of that said, I have a couple of questions :


1- From where else could this smell come from?


2- What could cause the engine temperature gauge to act weird?


3- Is there a possibility that the thermostat housing broke twice in 4 months? Could the garage who did the first reparation be at fault?


Thanks for your help!