Catch can.
What the catch can actually does is help out the pvc. our stock pcv isn't all that great and will eventually put oil back in the intake thru oil vapor. over time it will start to clogg up the intake and cause you to loose a bit of power. Most people put it in because it will help catch the vapor that the pvc system will let go back into the intake. Over 3,000 miles I have about a shot glass full of oil, that otherwise would be in the intake, or burned back in the engine.


