Late to the game but yes the connection to the intake tube is to let air into the crankcase so the block isnt in a constant vacuum from the pcv system.

and the black in the intake elbow is from the EGR valve. If you see oil the intake pipe then you have major blowby issues or a blocked pcv valve as you found

 

Apologies for my confusion....But which post are you replying to?

 

Multiple. None of them. Heck I dont know. I did t realize theyd be a quiz at the end

 

Sorry Aarcuda, didn't mean to seem rude!
I was just trying to understand if you were replying in regard to the title of the post (Oil Catch Cans)? I get your point; the low load breather allows metered air into the crankcase (preventing a vacuum from forming) when the PCV valve allows that metered air back out into the inlet elbow.

If so, I was just going to say that although oil catch cans may be useful to supercharged cars, my experience was that when I fitted one to my N/A car (far from reducing it) it appeared to promote oil loss through the PCV valve?

 

That does not make sense Esray. It is a passive device.

NA engines tend to have less blow by than SC cars so an oil catch can should catch less oil. It should in no way promote oil loss thru the PCV unless you have a leak in the way it was installed.

 

Thanks Jackra_1.

All I can say is that I installed the catch can because when I first bought my car I had a serious issue with OCCASIONAL white/grey smoke blowing violently from the exhaust; I mean violently! I mean blanketing all the cars around me!!
The fitted catch can filled within days. Correctly fitted. Correct pipe bore and correct pressure resistant pipes.
I was subsequently told that this smoke was being caused by the fact that one of the clutch drums? in my transmission had a crack in it and when the transmission heated up, the crack expanded and the drum expanded and jammed. The engine reacted to this by way of its electronic link with the transmission? I was told that it would be like I was doing 120 kph and suddenly changed to first gear? I mentioned this on our forum at the time and was told that this was ridiculous?
However, I replaced the drum and the problem went away, never to reappear?
I removed the catch can and my car now burns no oil whatsoever and has been running like a dream for the past year-and-a-half.
Obviously, I cannot vouch for the accuracy of what I have been told, but that has been my experience?
So in conclusion, you could well be right and it was not the catch can that was exacerbating whatever the problem I was having at the time??
In any event, perhaps a forum member following the aggressive Grey/White smoke thread will consider the possibility of a transmission fault (I think it was described as the A Drum?) as being the cause of his/her problem, as opposed to a failed PCV valve or the necessity for a catch can?
I don't know...I am not an expert - all I do know is that since then the first time I have had to put oil in my car was at its recent 10,000 kilometer oil change!

 

I agree a catch can can not increase oil burning thru that line. At most it can cause a vacuum leak.

but it can collect oil for long periods of time and then dump it periodically when it gets close to full and show oil burning smoke whereas the original system let the car ingest small quantities of oil continuously so you wont see smoke- bc its a tiny bit of oil spread out over time.