While cleaning the engine today at the body shop, I found this tucked away under the driver's side air filter.

I'm not able to trace the hose to see where it connects. It runs from the drivers side of the engine at the rear and then disappears in the middle of the back of the block.

Could this be the distributor vent?

 

Spot on, that is exactly what it is.

 

Distributor vent. It normally runs along that brace and sits on the inside fender.

 

Maybe help picture.