200+ miles on this mod and I continue to use oil. I'm going to keep evaluating this mod through my next oil change in about 2000 miles. We'll see what happens. So far, it doesn't look like this mod does anything but increase crankcase vacuum.

There is a ton of misinformation and misunderstanding in this thread. How do you have the catch can plumbed in? If you have stuck rings then increasing crankcase vacuum isn't going to help as much as it should with the oil burning. Maybe starting a new thread would be a good idea as this one is getting really bogged down and hard to follow.

Catch can is plumbed in between the PVC valve and the rear vacuum line that feeds into the intake manifold. It essentially routes the line that the originator of this mod ran directly to the rear vacuum port through a catch can rather than directly into the rear vacuum port on the intake.

I have considered stuck rings. Not sure there's a way to unstick them if they are other than pulling the pistons and installing new rings and I'm NOT going to do that to prevent the loss of 1 quart of oil every 1500 miles (average) or so.

The oil in the catch can is because of problems with the way the nipple comes off the valve cover and baffling. If you can create a bit more of a rise and/or pull from the top of the nipple (maybe add some of the fibre netting stuff) so that oil has a better chance to flow back it will help. Of course the flow you have from vacuum leaks(eg. rear main seal) and blowby the more the baffling problem shows up. Think of it as the catch can is supposed to be in the valve cover. The stuck rings I think can be helped by using premium gas and some aggressive driving. Works for me! :) The catch can is a good idea for checking on how the system is working but you shouldn't need it when you have things working reasonably well.

I can see only using one port on the vacuum manifold being a problem as well but not so much for your oil in the catch can.

Thanks for the input. I always run premium gas. Unfortunately, time and a wife that gets car sick doesn't allow me much aggressive driving. I need to get out on the freeway and blow it out!

HEY fifty- just want to let you know MrMcar from e46fanatics have used a liquimoly engine flush with good results- he outlined it in one of the threads @ E46fanatics if that should be of interest to you, try a search for his posts.
Good luck.

by the way , my E46 325XI touring is using the Bavarian Mod without a catch can and no oil consumption.4k miles now have not added any oil yet.

Thanks doc. I've been using their engine flush at every oil change for awhile now. I change my oil every 5000 miles and I run either 5/40 or 5/30 depending on the time of year. I tried 10/60 to see if it would cut my usage, but it didn't really. Lately, I purchase 10 liters of oil for an oil change and I can count on having to put 2 liters in before the next oil change.

Checked out a post by MrMcar. He recommends using a can of ERR and letting the car idle for half a day, then shutting it down, jacking up the right side of the car to level out the pistons and pour a can of ERR into the spark plug holes and let it sit over night. Then the next morning, crank it to get the fluid out of the cylinders and do an oil change. Run it with the new oil for 1000 miles and change the oil again. His experience with 3 M54 vehicles was that it appeared to unstick the ring packs and oil consumption went way down. I may give it a try. :dunno:

ANY body around here from the original authors of this MOD back in 2015 or any users of this MOD dating back to those early years COME Back report ANY FEEDBACK please...
Would like to know long term effects if any...good and bad.
I m running this MOD for past 5K and starting to see little drops of oil on my driveway.will be doing an oil change soon so i will be able to investigate where my leak is from .So far i cant see anything on top.

I've been running this mod for about as long as you. I don't have any oil leaks that weren't there before. I'm also using just as much oil as I was before the mod. The only small change I made to the mod was to run the post pcv line through an oil catch can. And it is catching oil. So, in my experience this mod has not delivered the promised reduction in oil consumption.