What is this ? 2013 Chevrolet Malibu 2.5 engine. Doing some work on my granddaughter's car and saw this opening, Has been like this for a very long time apparently with no noticeable symptoms. Looks like a pipe connects to something ???

 

One suggestion was that this was an opening for Turbo oil return line for the turbo versions of this engine. If that is correct then there would be a blocking plate for the non turbo engines. Any thoughts from others .. ??

 

If you probe the center hole, hhow far does it go?

 

Have not proned the center hole. Pretty sure it connects to the crankcase. With the engine running I could detect any air flow ... in or out. Would love to see a picture of another engine with whatever connects to the opening.