2016 Equinox "puffing" sound

[cinsco23]

I hear a puffing sound when shutting off the car.
It is the V6 engine.
I hear the sound right near the firewall in the middle of the engine.
Car also has a "small evap" leak but not sure if these two events occurred at the same time or if they are even related to each other.

 

[No Tyme]

My wife's 17 is a V6, and we have not noticed any sound other than maybe the fan shutting down. We are still under 50K miles on it and she won't give it up, as all the new ones at 4 cyclinder turbo's.
I am posting to follow this thread but for us no puffing sound.