why is my 2016 buick encore emitting a hot / burn - smell coming from the engine

What is your question?

I've had a buick mechanic look at the car and nothing jumped out at him - nothing visible. He noted that the coolant level was a bit low and topped it up for me. Since then, about two weeks later, I've noticed the coolant level is low again - (about 3/4" below the fill line). There are no visible leaks and no dripping on the ground, so it sounds like coolant is leaking somewhere internally like a crack in the head gasket perhaps. Are these buick turbo units cooled via the engine coolant circulation system? The car runs great - quiet and smooth so I'm thinking it's probably not the head gasket. My car only has 48K miles so warranty is still good to go.

What makes this problem better or worse?

hot smell is intermittent.

How long has your 2016 Buick Encore had this problem?

about 6 weeks.