What are some reasons why one should NOT do this mod?

He just ripped the stock CCV off the car, but installed nothing to replace the stock system (or the video doesn't show what's next). You can't rip the hoses off and just leave them open like that. You need to show the whole deal, not just partial video.

 

Found his stuff helpful before but this one seems to suggest misunderstanding of ccv operation e.g. leaving open port on valve cover.

 

I find that guy hard to watch. I recommend 50's Kid or Shop life for E46 DIY's.

 

Yes, those are my two favorite E46 channels.

 

Reasons not to delete CCV:

1. It's actually a pretty well-designed system, with it's cyclone design for oil separation. It DOES need to be replaced every 80k miles or so with a good quality part, preferably a genuine CCV valve.
2. Nathan at Nathan DIY is a bit of hack. He cuts many corners, and often doesn't keep cars for long.
3. Many people complain of catch can solutions.
4. the M56 valve cover IS a decent replacement for the stock M54 CCV

Here is a better video on how it works and the value of keeping.

 

Reasons not to delete CCV:

1. It's actually a pretty well-designed system, with it's cyclone design for oil separation. It DOES need to be replaced every 80k miles or so with a good quality part, preferably a genuine CCV valve.

2. Nathan at Nathan DIY is a bit of hack. He cuts many corners, and often doesn't keep cars for long.

3. Many people complain of catch can solutions.

5. the M56 valve cover IS a decent replacement for the stock M54 CCV

Here is a better video on how it works and the value of keeping.

If you can get past the skeleton hand, this is an absolutely FANTASTIC video and I'm really glad you shared. it. Thank you!

 

If you don’t live in an excessively cold climate and take lots of short trips then the ccv system is very good. It’s a very effective system, the only issue is condensation in the valve.

They even kept the design for later engines, adding a heater to the separator to prevent the condensation.

It lasts 100k ish miles. My original was still intact and working after 19 years and 90k miles.

Unless the CCV is giving you issues with blocking up then just replace it and leave the catch can

 

Some background for continuity;

The CCV/oil vapor capture scheme is NOT unique to BMW. Every car maker has a version of such fitted to any modern ICE.
This was borne out of tightening emission regulations. Crankcase fumes must not vent into the atmosphere. Same for fuel vapors from the fuel tank, all the way up through the injectors; albeit that's the EVAP system.

So the all too familiar CCV that's discussed here is the regular or cold climate (much preferred by me) version. It does work fairly well, however like anything else on your car it DOES NOT last forever.
Then folks go chasing codes incorrectly, replace a bunch of parts (not CCV related) and codes can sometimes persist. Then more parts get thrown at the car and finally the CCV system was found to be a major contributor to the running issue.
Out of frustration it then gets labeled as a complete POS. Unfair I say because of bad diagnostics. Then folks spend hours doing a modification(s) to eliminate the CCV system. Some successful, others not. Well documented if one searches the posts here.

Lets have a very brief look at how it works; First and foremost the piston rings must be clean and floating to ensure that the engine not only makes good power, but also produces good vacuum and controls oil burning. (Both erstwhile endeavors, no?) Since the CCV system captures the vapor inside the engine and then separates the oily vapor and condenses it, then sends it back to where it belongs; in the oil sump. The (mostly) air vapor is returned to the intake, mixed with the incoming air/fuel and processed by the catalytic converter/oxygen sensors.

If your rings are "coked" up not only are you burning oil, your engine will be lower than threshold for vacuum. Since the CCV system has no electric motors for activation, it uses engine vacuum to make the above operation happen. Furthermore since the CCV system is trying to separate the oil vapor from air vapor AND since your rings are NOT clean, you will produce copious amounts of the undesirable oily vapor. When combined with an old and tired CCV system, it becomes overwhelmed.
Also diaphragms can crack from age, short tripping makes mayo, and drainback tubes become clogged.

There's many ways to check into some information about why your car is not running right. Evaluating fuel trim values, checking (use a smoke tester dammit) for vacuum leaks (remember I said that the CCV system uses vacuum? Therefore if you have a vacuum leak, it's NOT going to work properly!) and having a look at things like fuel pressure and compression health of the engine.

Switch to a M56 valve cover and install a catch can? Sure, but keep in mind you're band-aiding an underlying issue. That also presumes that you've done it correctly and NOT pressurizing the engine??
Tantamount to installing the wrong plugs and coils into the car, it's likely not going to work correctly.

It's a simple system, and may need to be replaced once, maybe twice during ownership. What's the big deal? One wouldn't scoff on two fuel pumps, a couple of water pumps and/or thermostats, BUT the CCV, oh it's a piece of shit. I don't get it?

When a car comes in here for a running fault and/or smoking, we must establish some basics FIRST!
What's the engine vacuum?
What are the fuel trims?
What are the fault codes?

Then we must move forward with the "3 C's": Complaint, Cause, Correction. With a heavy emphasis on the later two.

Looking at fuel trims, making logs and having NZ read them is generous and nice. However the fuel trimming is a continually adaptive scheme. If you haven't checked the basics first you might be replacing many parts that don't deal with the root of the issue, but only addressing the symptoms?

Get the rings clean with SAFE oil & additives, renew the CCV if it's more that 100K miles, clean the double wall dipstick and replace ALL the CCV hoses. It will give you good service.

Rant OFF....

 

BUT the CCV, oh it's a piece of shit. I don't get it?

This usually gets said after trying to snake in that hose from the manifold to the separator.

F**ks my knuckles up every time

 

Keep in mind that many when doing a CCV replacement try to remove the old parts neatly. It's just about impossible. Just (carefully) bust the damn thing up. Then remove the bits.
The new hoses are pliable and are a different animal from the old dried up ones.

 

after having done just 6 replacements of these, i actually dont consider it a POS anymore and have stopped cursing while doing the replacement LOL

 

I'd agree, the oil control rings are a bigger problem than the CCV.

That said, while the design may be ok, the execution is pretty... plasticky.
Which is not to argue that everyone else didn't do it, just that it's
certainly built to a cost that the rest of the car exceeds.

t

 

Yeah if it was solid metal it would be better, but it is a difficult part to engineer as a metal part. They probably considered it but the manufacturing and tooling cost was probably too much to justify it, so they went with plastic. Not saying they couldn't have made it better. But they don't make cars like they used to.