My wife's 2012 chevy equinox with the 2.4l ecotec engine. The PCV valve was completely clogged not letting the gases circulate to the air intake, and trapping moisture in the hose causing it to freeze during the winter. Which could lead to blown rear main seal. I Cleaned it with B12 carburetor cleaner.

GM bulletin 14882 regarding this PCV valve problem.

!!!WARNING!!!
I'm not responsible for any damage to your vehicle if you try this is at your own risk.