shaun

hey guys i got a question for you.
when the car is running and you remove the oil cap is the idle suposed to change?
could thins be because of my catch can? is it set up right?
help me out guys i dont want to be hurting my engine.

LS1-450

iTrader: (33)

It's because of the additional un-measured air entering your engine. Because the PVC system is connected to the intake &/or valve covers/valley cover, when the oil cap is removed, the intake is sucking additonal, un-measured air into the engine through the oil fill opening. Air travels into the oil filler & then either out a valve cover, into the intake or down the push rod clearance in the heads/block, into the crank case, out the crank case through the valley cover & into the intake, depending on your PCV routing. None of this air passes through the MAF, so, it leans out the mix & changes the idle RPM. It's actually a sign that your car is still making good vacuum.

DaddySS

Or stated differently, it's a vacuum leak and exactly the way it's supposed work with a closed PVC system like ours.

Lopoetve

iTrader: (1)

dot for future

shaun

i tryed uploeading a pic but it dident work so take a look and tell me if this is ok.

teke184

iTrader: (5)

looks good to me.

hose from the TB to the front passenger side of the valve cover
hose from the rear of the drivers side cover, into a T then the other side of the T going to the rear passenger side valve cover. then the outlet of the T running up into the catch can, and then into the vacumm port on the intake manifold.

was thinking you wanted the PCV valve between the can and the manifold. not sure.

shaun

im not shure.
can any one help?

DaddySS

You have the lines on catch can reversed and yes, PCV between the catch can and the manifold, not before it like you have now. the PCV placement doesn't make a huge difference but you basically want the fumes unrestricted running to the catch can lower connector. Then vacuum through the pcv to the upper connector of the catch can.

shaun

That's wierd most of them I have seen on here where set up like mine
Can some one confirm this so I can set it up right

LS6427

iTrader: (2)

When I take my cap off with the engine running, absolutely nothing at all happens to my idle.

bonestock99

iTrader: (1)

May be a faulty pcv valve.

DaddySS

Look at it this way - you don't want the intake drawing from the bottom were the oil and condensation has gathered, you want it drawing from the top of the catch can after the wire mesh filter. So you want the oil and steam to enter the bottom, be filtered by the mesh and then cleaner air drawn from the top.

DaddySS

I stand corrected. I looked up the manufacturers install instructions, they have the dirty air from the engine entering the top and the cleaner air from the side of the catch can going to the intake. Sorry for the mistake.