Oil in Plenum, how much is too much ?
Oil in the plenum? That must be why most of us install "Oil Catch Cans!" Even the HomeDepot catch cans work very well to keep oil where it should be, not in your breather system.
PVC valve should be checked at every 30K mile service....Gary
PVC valve should be checked at every 30K mile service....Gary
I agree with you. I've installed them on my own personal cars to keep oil out of the breather system and in my oil pan where it belongs.
I was just stating that nearly every time i pull an intake manifold apart on some average, high-mileage car a friend needs help fixing, i find the same burnt orange residue in the pictures the OP has provided. I've seen entire engines with the internals stained bright orange like that...not just inside the plenum. Was really common and expected. To be honest i bet if we pulled the plenums off most G35's with high miles, we'd see the same residue inside the plenum.
I was just stating that nearly every time i pull an intake manifold apart on some average, high-mileage car a friend needs help fixing, i find the same burnt orange residue in the pictures the OP has provided. I've seen entire engines with the internals stained bright orange like that...not just inside the plenum. Was really common and expected. To be honest i bet if we pulled the plenums off most G35's with high miles, we'd see the same residue inside the plenum.
Last edited by Mustang5L5; May 24, 2013 at 11:54 AM.
Recently installed my 5/16" copper iso thermal plenum spacer and here is a picture of the oil in my plenum.

What do you guys think?
I've read about the PCV valve needing replacement but I can't seem to figure out where exactly it is. I looked at pictures of DIY's but they're not very clear.
I'll also be looking into getting a catch can eventually as well.

What do you guys think?
I've read about the PCV valve needing replacement but I can't seem to figure out where exactly it is. I looked at pictures of DIY's but they're not very clear.
I'll also be looking into getting a catch can eventually as well.
Joined: Mar 2009
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From: By the sea, Tx
G35 sedan w/ too much money in mods

If you are standing in front of the engine, the PCV valve is on the passenger side of the motor close to the front of the car. It has a hose that runs to a metal tube sticking out of the front of the plenum, hard to miss. It literally took me 4 minutes tom replace mine, super easy DIY.
Recently installed my 5/16" copper iso thermal plenum spacer and here is a picture of the oil in my plenum.

What do you guys think?
I've read about the PCV valve needing replacement but I can't seem to figure out where exactly it is. I looked at pictures of DIY's but they're not very clear.
I'll also be looking into getting a catch can eventually as well.

What do you guys think?
I've read about the PCV valve needing replacement but I can't seem to figure out where exactly it is. I looked at pictures of DIY's but they're not very clear.
I'll also be looking into getting a catch can eventually as well.
If you are standing in front of the engine, the PCV valve is on the passenger side of the motor close to the front of the car. It has a hose that runs to a metal tube sticking out of the front of the plenum, hard to miss. It literally took me 4 minutes tom replace mine, super easy DIY.
The engine bay:

&
The PCV valve:

So is the PCV valve at the end of that black rubber hose or...?
the valve is screwed into the valve cover. and the hose connects the valve to the neck on the manifold
Did my PCV 2 years ago when I thought it was my reason for consuming **** tonnes of oil. It's very simple to do.
BTW, my plenum never looked as bad as the ones pictured. Especially that last one....waaaaaaaay too much oil being brought back in to the plenum there.
BTW, my plenum never looked as bad as the ones pictured. Especially that last one....waaaaaaaay too much oil being brought back in to the plenum there.
Just checked my PVC valve this last week, with 48K miles on SLICK the valve was still working correctly. If you shake em and they rattle you're in good shape. I used carb cleaner to clean it out of any deposits and reinstalled....Gary
Another way to tell if your PCV valve is gone or on its way out is to listen to it while idling. If you hear a loud hissing noise coming from it while the car is running, there's a good chance it needs to be changed.
Heard mine while I was bleeding the coolant on my car a couple of weeks ago so I got a new one from Nissan for $18 and changed it out in about 20 mins.
Heard mine while I was bleeding the coolant on my car a couple of weeks ago so I got a new one from Nissan for $18 and changed it out in about 20 mins.








