That's the only thing I thought it could have been too..

If you pull that hose out from the bottom there should be the PCV valve on the end of it (or still in the hole you pulled the tube out from).It's a plastic valve with a ball bearing in it.Give that a good clean up and put it back.

Just remember where you pulled the hose/PCV from as you cant see it,so just feel it out.Use a torch!

Unclogging the PCV will help your car breath better.