Originally Posted by hondatech
Air is not "pulled" into the valve cover from the intake tube. You are confused I think.
Yes, it is. The other end of the PCV system is on the underside of your intake manifold.
The intake manifold always has lower pressure than the intake arm (more vaccum) and thus when the PCV valve is open, air will move from intake, into crank case, then up into your IM.