Crankcase negative presure / vacuum. Where is the PCV or CCV ? is it Clogged?

[Rlequerica]

Good morning friends:
My car is a 2009 328i E90 Sedan N52B30A engine with no turbo, manufactured in Rossylin/Pretoria SouthAfrica, and I cannot see the PCV valve.

1. Does my car has a CCV instead?
Is it invisible, because it is under de Valve Cover?
If so, how is it connected to the PCV system hoses throug the crankcase?
How do I know if those hoses are clogged?
Are these hoses going to the intake?
Before or after the throttle?
How are those gases cooled down before entering the intake?
Is that why the intakes have carbon soot that has to be removed with walnut blaster?

2. The issue is that my Valve Cover’s gasket and Filter housing are leaking, and I suspect it is for overpressure in the crankcase due to the obstructed PCV or CCV, I don’t know which.

3. I Find strange that when opening the engine oil fill cap, while the car is idling, there is a sucking force, so there is vacuum in the crankcase, I was expecting the opposite.
Same when the engine is cold that when it is hot.

Should my crankcase pressure be positive or negative / vacccum ?, and
For what reasons could it be negative?

5. Could my AC cold air becoming hot intermittently be related to crankcase presure sensor?

thank you.

[bmwdirtracer]

Welcome to the forum.

If you have a plastic valvecover, the oil separator is built into the valvecover. Has the gasket been changed ever? They leak very frequently; I've changed 2 just this week. There is supposed to be a mild vacuum in the crankcase; that's how the ccv works.

The oil filter housing leaks more often than the valve cover. Make sure you change the oil cooler gasket attached, if your engine has this.

The walnut blasting is really for direct injection cars.

For the a/c, have the system evacuated and recharged with exactly the correct amount of freon, have codes checked in the IHKA computer, and use compressed air to blow out the vent for the sampling fan.

[dworthy]

Very small writing, had problems reading it, but here is what I could read/understand:

1) Yes, that car has a CCV and it is part of the valve cover IIRC. And you should have suction or negative pressure if that makes sense.
How the system works, is it pull vapors from the top of the valve cover, send it into a cyclone valve to separate the solids from the vapors. The solids get sent back to the oil pan while the vapors are put back into the intake after the throttle body.
Okay what is being used to test it? AFAIK there is ONLY 1 way to test a CCV system: Slack tube manometer. It is read in Inches of water, and nothing else. If you got a guy out there with a vacuum gauge trying to read the crank case pressure, find a new guy.

2) Nope, that is call "Old Age". The valve covers are only good for about 8 years if you are lucky. On the M-5x and N-5x motors, it is a known problem with those spots leaking, and a decent BMW tech would know this.

3) There is no need to open the oil filler cap while the motor is running.

4) Must have missed that one....

5) Like Chris said, get the system evacuated, vacuum pulled and checked for leaks.

[Rlequerica]

Thanks very much for answering my needs.

Good morning friends:

I have a plastic valve cover, and the gaskets have not been replaced.
Is the CCV, under or above. (In or out) de Crankcase or Valve Cover?
How can I use a Slak Tube Manometer without removing the Valve Cover?

If the CCV is inside the crankcase how is it connected to the PCV system hoses throug the crankcase? Another gasket or seal?
How do I know if those hoses and CCV are clogged?

Is it possible to replace only the CCV diafragma to avoid expending in the complete cover? I understand the CCV and the Valve Cover are integrated and cannot be pulled apart.

How are those gases cooled down before entering the intake?

Are there two separated gaskets, or is it the same? Oil Filter Housing, and Oil Cooler.
How coul I find out if The car have or don’t have an Oil Cooler? I cannot find it, because I don’t know how it looks like.


Is cyclone valve same as CCV?
What is the meaning of acronyms:
IHKA ? IIRC ? AFAIK ?

I checked that My AC for no leak and recycled the gas, that is why I am looking for causes in the Temperature or presure sensor.

thank you.

[dworthy]

I am not sure how you are doing it, but the size of the text is like 4 point. Please make the effort to increase the size of the text as it is very hard to read.

[Rlequerica]

Good morning:

CHRIS: Thanks for your help.
Does my car is direct injection? I have no clue.
For the a/c, the system was evacuated and recharged with exactly the correct amount of GAS on Jiffy Lube ( i don't know if freon)
First I will use compressed air to blow out the vent for the sampling fan.
Is checking the codes in IHKA computer, made only at dealer service?

DARIN: Thanks also for the heads-up on font size. What font size would you recommend; On my screen #4 looks humongous, when I use #2 or #3 on my screen is very similar to everybody else.
Not to purchase the entire valve cover (It is almost $400), has anybody "clean" the valve? Or replace the inside diaphragm ?

I found that in a 2009 328i E90 non turbo Engine N5B30A:
- Tthe CCV is integrated outside the valve cover (111 275 522 81) between spark plugs #5 and #6; and the hose inlet that feeds the CCV is located in the valve cover rear upper corner, in the passenger side.
- The PCV system has only one "Y shape" hose: (111 575 595 28); One end plugs into the Valve Cover inlet.

I am trying to figure out how are the solids and oil diverted in one side of the "Y" going to the oil pan, and the gases into the other "Y" end into the Intake after the throttle. Probably a filter or dripping valve in the center of the "y".

If the entire plastic valve covers are only good for about 8 years.... i shall not replace only the gaskets, that would be throwing money in a hole.

[dworthy]

No you do not have direct injection, as only the N54/5 motors come with it.
Jiffy lube? Well they should have the proper fill amount, but for using them to diagnose anything...... well I find it hard to say anything nice.
For checking codes, and good Independant Euro shop should be able to fill this requirement.

What I mean by 4pt is like using MS Word, as I don't mess with the editor here, so it look like size 1.

Get the CCV tested first before you throw a valve cover at it.

I never said the plastic was only good for 8-years, it will be the rubber gaskets that are only good for about 8 years.

[02Pilot]

Yes you do have direct injection, as all N5X motors come with it.

You sure about this? I haven't torn that deep into my N51 yet, so I can't say from personal experience, but according to everything I've read, including Bentley, the N51 and N52 use conventional injectors, while the N54 and N55 are DI.

[dworthy]

I was referring to the N-54/55 motors, and you are correct the N-51/52 has normal injection. That is why they don't have the issues with dirty valve, ect.

[bmwdirtracer]

Yup. The N54/55 turbomotors have DI, the others don't. Although DI may save fuel/ make more power, I don't like walnut shells.

[Rlequerica]

PCV (Positive CrankCase Ventilation) System, on a
2009 BMW 328i E90 N52 SEDAN,
with CCV (Crankcase Cyclone Valve), (Cyclone=oil separator=oil catch can), and breather integrated in the PLASTIC VALVE COVER.

Once removed the COVER OF THE camshaft housing ( top side of the cylinder head); to replace the COVER gasket, and CHECK if the CCV valve, breather, oil separator and hose are working properly.

1. Disattaching the hose that goes to the intake, from the CCV outbond nipple, I freely and effortless blowed and sucked air (with my mouth) in and out of the nipple.
Is it normal for the valve to allow two ways flow? Or higher pressures are required for the valve to operate?.
Mis it true that the diaphragm inside the CCV, should not close completely? , except when backfiring; and should keep in factory adjusted variable openings according to engine running conditions?

2. There is a plastic tube (1/16” x 1/2” ?), a port not connected to any hose, located on the COVER’s exterior top side, over the glued plastic lid of the integrated CCV’s “diaphragm compartment”.
This port is sealed in some models, and in others creates a 50 to 54 psi vacuum from the gas pressure regulator, in case the gas regulator fails, the gas vapors be conducted to the engine intake instead of going to the atmosphere.
I’m my car model the port is open to both ways airflow, I don’t know if it is because it is damaged.
How do I know if my car model shall have they hose towards the gas fuel regulator?
is that the cause for BMW Recall on CCV valve heater that is getting cars on fire, even when parking?

3. The integrated oil separator (oil catch can) is made of two deep plastic pockets located hanging on the inside of the COVER, between spark plug holes 2 & 3 an 4 & 5. (Marked with arrows in the attached picture)
The pockets attached to underside of the COVER, have passages for airflow going from the camshafts housing into the pockets.
The pockets extend deeply down nearly to touch the bottom of the Camshasfts housing, and have two drip valves, one for each pocket, to return the oil back to the bottom of the camshaft housing.
I was able to suck air from both pocket’s drip valves ( with my mouth), but I was only able to blow air inbound one of them, probably that valve allowing me to blow is not working well or stuck with oil gunk. After I cleaned the oil gunk with kerosene that drip valve improved sealing, and I could not so easily blow air inbound towards the pocket.

If those drip valves (check valves), don’t work well, and the CCV diaphragm is stucked or ripped, oil droplets will full the pockets ( oil catch can) and send them to the intake, clogging with oil gunk all the trajectory. I that will increase the camshaft housing pressure and blow the valve cover gasket, and will further form oil gunk in the crankcase, and further block other engine oil passages.

On the exterior top of the COVER, is a glued integrated plastic lid that would be the roof / ceiling of the pockets, that lid contains interconnected horizontal tubes embebed within the skin of the COVER conducting airflow towards the CCV Valve’s nipple towards the hose connected towards the intake. All those interconnected tubes were full of oil gunk.

4. I filled with kerosene for couple of hours the oil separator pockets, the drip valves, the diaphragm compartment, the interconnected tubes, and the CCV valve outbound Nipple to remove the heavy oil gunk and unclog the System.
I found that one of the two pockets on the lower tip, close to the drip valve has a crack maybe from forcibly removing the COVER, from the camshafts housing (or burnt if it touched the camshaft housing bottom)
I will try to repair it with glue... But I am afraid that the positive presure in the camshaft housing and air flow, plus the succión from the intake, maximized because of the failure of the CCV diaphragm Will send oil droplets to the interconnected tubes, the CCV valve and the hose towards the intake.
The link below, shows a video of the cover details. WATCH ALL THE ADDED VIDEOS.


https://m.youtube.com/watch?v=6NCJFw55hPY

1st picture shows with arrows, the pockets and its drip valves, one pocket presents a crack.
2nd picture shows the bottom of the Camshafr housing, where the pocket tip accommodates.
3rd snd 4th pictures shows the pockets tip with valves, and the crack can be evidenced.
5th picture shows the interconnected horizontal tubes embebed on the COVER’s skin.... an yes they got clogged, and I cleaned it with kerosene flow and shaking.

https://m.youtube.com/watch?v=-p5n4ei4KNg

https://m.youtube.com/watch?v=zsQokuR_7oM

https://m.youtube.com/watch?v=5rs1rnVnXhY

[dworthy]

Oh man that motor is nasty!

So this is what I would do as it seems to me that your motor is sludged up quite a bit:

1) Purchase some Dexron ATF, yes Automatic transmission fluid. Not worried about the brand, type, ect. as it is what will clean out that motor slowly.
2) Pour about 1/2 a quart into the motor, and go for about 100 miles worth of driving, not worried if you do this in 4-7 days.
3) Change the oil filter, then pour the rest in. Go about the same mileage, then change the oil and filter.

Lastly you can look for a used valve cover or attempt to repair the hole in the CCV I see in Photo #4.

[bmwdirtracer]

Could be worse:

https://www.youtube.com/watch?v=Y-qJkuyCkPw

You seem to have arrived at the same solution that Darin and I would have, although by a different means. We'd have tested crankcase vacuum, using a modified oil filler cap, and a slack tube manometer.

All that said, a big hole in the CCV system is both an intake leak, and a malfunctioning CCV system.

Darin's absolutely right that you need to clean the sludge out of that motor. It has had neglectful oil change intervals. ATF has excellent detergents, and will slowly and safely eat away those sludge deposits, making your engine clean again,as well as preventing future CCV issues.

Oh, don't use kerosene on pieces with diaphragms in the future. No big deal, this time, since you're replacing the cover, but solvents eat the thin diaphragms. The detergents in ATF are far safer.

Good job of finding the issue, and the solution, and thanks for sharing here.