mlrtime99

So there's a pcv valve only on the passenger valve cover, and as far as I can tell the ventilation hose on the driver side valve cover is wide open to the intake.

Anyone figure out the engineering reason for them no placing a pcv valve on both valve covers? I'd assume if there's crankcase pressure on one head it would exist on the others. Just figuring out why my intake is so damn oily.

MudHippy

I believe it's that way for a reason. And I wouldn't fool with the notion of putting another PCV valve where the ventilation hose is. Or mess with the ID or length of the ventilation hose. It's probably a finely tuned system, designed with a specific purpose and function in mind.

What you need to do is some research on what's called a "PCV oil catch can". I haven't even considered it myself, but I'd heard of the idea. So I thought I pass it on to you.

Good luck!

mlrtime99

Hadn't planned on changing it, just wondering. I believe if we do treat it like a finely tuned system even adding a catch can would create some restriction and anger the Yota gods.

In reality most of the blow by/oil mist LOOKS like it comes from the passenger valve cover (guessing by my intake runner condition), but the emissions diagram shows fresh air and blow by flowing through both hoses. Not sure what magic is at work but it's working!

MudHippy

The PCV valve is a one-way valve which is designed to flow in one direction, from the crankcase to the intake plenum chamber. No fresh air will enter the crankcase(or the intake plenum chamber)through it, and/or the hose connected to it. The vacuum in the intake plenum chamber during engine operation would also prevent that from occuring.
A full explaination of the PCV system using a variable-flow PCV valve, and it's purpose, can be found here: http://www.autoshop101.com/forms/h63.pdf