Seeker1056

I have read hundreds of threads and googled pics without any clear answers

pcv valves - where are they on an lq4 - hidden in the valve covers? - as I can not find one or more on the motor anywhere?

why the puke tanks - do the pcv valves not keep the oil in the motor under boost or high vacumn?

would one benefit from additional inline pcv's or one way valves in the two valve cover lines?

I have seen enough diagrams and threads on how to plumb a puke tank so no worries there - just dont wish to spend money better spent elsewhere if its not really a necessary install
thanks

Black89Z51

iTrader: (2)

Driver's side valve cover in the back behind the last coil I believe.

Boost can pressurize the the crankcase and since the PCV is a vacuum system routed to the intake, it has no where to go. You have to vent it somewhere or the oil will find another route.

If you want to run PCV (which I don't recommend since the oil mist gathers in the intake track and can deposit in the combustion chamber) you have to run a check valve on the vacuum line, but there is a good chance that the crankcase pressure will push the PCV valve right out of the valve cover.

Seeker1056

if the pcv valve is doing its job properly there should be zero boost in the crank case
never had this issue on any other kind of boosted motor i have run - so why on the LS?

alocker

iTrader: (10)

There isn't one, it's a tiny hole in the driver side that meters air, no valve. You need to put a check valve in if you have any part of the intake going to the valve cover.

Seeker1056

the other thing I noted is that there doesn't appear to be anywhere for air to enter the crankcase to balance the pcv system
is there enough piston blowby that a crankcase vent isn't required due to the little orifice size?
otherwise I would think one would be collapsing the front or rear main seals
I did note that on the passenger side hose that there is oil present on the inside of the hose
sounds like a very poor setup? or am I missing something

alocker

iTrader: (10)

The air enters in front of the TB on the pass side valve cover port. Driver side goes to intake. This can be revered though. FI requires a higher capacity venting though. Most run a large vent to atmosphere from each valve cover.

Seeker1056

on my 2003 van 6l the rear drivers goes to the top of the intake, and the passenger side goes to a fitting behind the throttle body on the side of the intake which is why I am totally confused as to how this factory system works

but no worries - I will put one inline pcv valve on the drivers side, and will add an atmospheric vent on the passenger side and block the small factory passenger valve cover vent so I don't have to worry about pressurizing the crankcase.
thanks all

alocker

iTrader: (10)

How much boost do you plan to run. One vent may not be enough to keep your seals intact.

Seeker1056

12-15 psi
having said that - unless there is severe blowby on the rings there will be zero boost to my crank case when I am done with the new pcv system.
I can add a second pcv valve if necessary???
A single 1" filtered air vent should be more than enough relief for the pcv valve(s) and any blow by

Old Geezer

iTrader: (3)

http://mightym0use.wix.com/mm-solutions