[oZades]

Anyone have issues with external pcv catch can barely collecting anything? My boost side can fills up 3x the amount. Low side setup is blocked head ports with rb external pcv to a catch can and vacuum from throttle body.

[Rob@RB]

This sounds way off as usually it is the opposite- the high sides doing next to nothing and the RB low side catching all.

Send an email directly and will see if we can see something awry with your setup.

[onebluemcm]

Rob doesn't need any backing up on this, but it does sound reversed. On mine, I'd estimate the rate of fill around 10:1, low side vs high side.

[jcortez75]

Owner perspective (not a mechanic): if your low side can is barely collecting, I’d check routing/check-valve orientation and tiny leaks first. Even a slight vacuum leak can change behavior a lot.

What helped me troubleshoot mine:
- pressure/smoke test for leaks
- verify valve orientation and hose routing
- inspect for collapsed/soft vacuum lines near heat

Helpful tools I used:
Vacuum/boost line assortment:
https://www.amazon.com/s?k=silicone+...tag=2nspira-20
Hose clamp pliers (makes re-routing/checking way easier):
https://www.amazon.com/s?k=hose+clam...tag=2nspira-20

If you want, I can share the quick checklist I follow before deciding the catch can itself is the issue.

[Rob@RB]

Just FYI that the cure was found on this one, the low side OCC drain plug was not installed.

[oVeRdOsE.]

Originally Posted by Rob@RB

Just FYI that the cure was found on this one, the low side OCC drain plug was not installed.

easy one !


in my case, coming from audi world, I also found the CC on high side dont catch much.

N54s seems to be pretty solid on that, the exhaust tip can take up to a month -500km to get black. While my audi it takes around 30km drive and all black.

and when I did the single turbo conversion I lost the vacuum on the can, thus not much oil on the can

[onebluemcm]

Originally Posted by Rob@RB

Just FYI that the cure was found on this one, the low side OCC drain plug was not installed.

How did that not result in a vacuum leak and a host of other problems

[Rob@RB]

Originally Posted by onebluemcm

How did that not result in a vacuum leak and a host of other problems

This is exactly what I'd said during our discussions...

"The lack of oil collection in the low side OCC is extraordinarily odd, in fact so odd that I’ve never heard of such a thing in over a decade of selling these kits. This is so odd that it makes me wonder if say the drain plug missing in the bottom of the OCC? Although that would make the engine run pretty bad with a big vacuum leak, such that the running bad in itself would be a bigger concern that you’d likely be looking into first and foremost."

This led to a response of there being an issue with the OCC drain plug being "very loose" and that after properly securing the drain plug all is now well.

As such I should correct myself on my last post as the drain plug WAS installed but was not tight. This would still create a vacuum leak but perhaps just friendly enough of one to not lead to serious engine running issues? Whatever the case the OP reported all was good now with the simple fix.

Rob

[onebluemcm]

Great outcome then. Yeah, makes more sense that it was loose vs long gone with an effective gaping hole there.