I just started the timing chain job on my friend's 05 and wanted to follow up with some more info regarding the PCV system.
The first picture above shows where the fresh air for the PCV system comes from. There's a fitting on the air boot after the MAF that allows filtered air to enter the driver's side valve cover.
This second picture shows the other end of that hose connecting to the valve cover, it's just rearward of the last coil on that bank. If you note the convoluted tubing with the white label, that's the hose and it goes to a 45 degree fitting coming out of the valve cover that is under the brake booster vacuum hose shown in this picture above.
If you'll look at the intake plenum, there's a black hose that enters both sides of if, just below the shiny freeze plug looking component.
Spray the fitting down with some sort of lubrication and take a flat blade screw driver and twist it out. Be careful and use plenty of lube because the o-rings on this orfice tube can tear on the not-so-smooth aluminum plenum. As you can see in this picture, there's a little bit of orange still in the opening. That's where the o-ring tore a little bit.
On it's way out you'll notice that there's some resistance because of the length that it extends inward as well as the rear sections of the hoses being bolted down. See below pic for the rear section being unbolted from the backside of the intake plenum, just rearward of the brake booster hose which has the blue paint on it:
With the orfice removed completely from the intake you can look down in there with a flashlight and see that there's really not a lot of restriction in there (hopefully)
Above you'll see the where this other end of this vacuum related PCV hose seats on to a fitting from the passenger's side valve cover, just above the yellow fuel line label.
This picture shows the complete VACUUM side of the PCV system, upper left where it goes in to the passenger side valve cover and the there's a "T" on the backside of the intake and the hoses continue up to the middle/side of each bank.
The part that attaches to the passenger side valve cover has a spring loaded clip (it's just plastic that is bent to provide the spring action) that has to be carefully released to prevent it from braking, see pic below:
They split the vacuum hose portion so that, in theory, one bank alone is not saturated with all of the crank-case fumes/vapor/oil. Also, there is no function PCV valve like we're used to seeing, no check valve, spring and ball or whatever. It appears to be a restrictive hose where the diameter itself meters the airflow. With the vacuum side PCV hose off you can suck or blow in to any end of it the flow is the same and does not become blocked like a check valve would.
The underside of the intake plenum shows that oil is definitely making it's way in to the intake stream causing the oil consumption that we've been chasing since he bought the car used a year or so ago. The mileage on this model is just over 75,000.
Additionally, below you'll see two pictures of the spark plug. The first picture shows the white crusty build up that you could expect to see in an engine that has excessive oil making it's way to the combustion chamber.
This second picture shows the same plug rotated 180 degrees. Based on the lack of deposits on this side it would be easy to believe that the first side is the side facing the intake port itself where the oil would contact first and the second is cleaner because of the lack of exposure.
The last two pictures show the intake manifold itself, still attached to the engine. It's pretty clear that one bank has been exposed to more oil than the other but I really don't have an explanation as to why nor do I have a decent plan for reducing the problem. You can also note where the two hoses come together as one and then lead over to the valve cover. Also, it's important to note that if you plan on doing something with the PCV system you'll need to remember that you're dealing with a Mass Airflow Engine Management system. This means that any attempt to vent the PCV system, add in a catch can with a filter or stick one of those cool little air filters that fit on your pinky on the valve cover then you may create a fuel trim issue leading to a Rich/Lean condition. In other words, if you add in a catch can, it has to be sealed and only pulling air from the properly sealed up valve cover and getting it's fresh air from the post-maf filtered air.
Additionally, the PCV hoses shown above can become brittle on high mileage cars. The convoluted sections will become brittle and won't like to bend out of the way. Additionally, the softer rubber boot that goes to the driver's side valve cover will become softer and may not be a tight seal on high mileage cars as well. This again can cause a MAF trim issue and the solution will be to either replace the hose with a new one or put a hose clamp on it. From my experience, the hose clamp can work good for a while but if the boot is ultra soggy to begin with, the clamp will cut the hose and cause it to fail as well. Finally, if you don't use an OEM replacement hose and try to piece it together with hose from the parts store then you should know that not all hoses are equal. I've work on quite a number of cars where people put heater hose on where PCV hose was used before. This looks and fits fine for a while but give it a year or so and the hose that works for coolant will swell up the longer it's exposed to oil and crankcase vapors.
Doug