Planning to fit an oil catch can into my car. Any problems with this setup?

Question

I own a 2007 Ford Fiesta ST150, I have modified it a little, one of the mods is a cold air intake.

I want to install an oil catch can setup, but as the PCV vent is behind the intake manifold and requires the entire manifold to be removed to access it, I wanted to post my plan here first to make sure it will work before I pull anything apart.

My engine has two PCV valves. One is the upper crankcase breather, which routes back to the air intake. The other is the lower crankcase breather, which routes back into the intake manifold.

Here's a picture of the upper crankcase breather (actual photo of my car):

The crankcase breather is circled in pink, and the point where it enters the intake is circled in green.

Here's a photo of the lower crankcase breather and the hole on the intake manifold that it leads to (not my pictures):

The important point is circled number 1.

Now you have the full picture of the PCV system on my car. Here's a drawing of what I plan to do:

It's pretty easy to understand, but the idea is to route a tube from both the upper and lower breather vents into the oil catch can (either using a t-join, or by using a dual inlet catch can). Then, I have tube from the outlet of the catch can, to a t-join, which splits and leads to the CAIS and to the hole on the intake manifold.

My question is, are there any problems with this setup? Will it work? Is there anything I haven't thought about?

Answer 1

I would assume, from inspection and not knowing your vehicle, that the upper and lower pcv's operate at different pressures (depressions really as below atmospheric) otherwise they would have had them joined together already...