[DrivenByE30]

My car is a 2012 F30 335i (N55), it has about 99,300 miles.

After 7-8 years, the PCV/CCV on these cars will usually fail.



The failure is due to the thin orange plastic membrane under the PCV/CCV cap, which is at the top of the Engine Valves Cover.

PCV = Pressure Crankcase Valve
CCV = Crank Case Valve



The symptom to this failure is usually either:
- hissing noise at the top of the engine due to the air being sucked into
- idling of the engine is irregular, and sometimes engine would shut down, similar to as if you had left the oil cap slightly loose or not fully tighten...

The purpose of this membrane is to maintain a sealed vacuum within the engine, and yet to allow the pressure to change without damaging engine components.

A crack membrane (failure over time) compromises the vacuum of the engine, and thus the engine will have difficulty working.

The normal way to fix this is to have the entire Engine Valves Cover replaced, which can cost anywhere between $170 to excess of $500 depending on which brand, official or knock-off you buy, and labor at the dealership can vary between 2hours up to 5hours ($200 to excess of $500).



For $15, you can fix it yourself, this job is only 5 to 10 mins long, but if you are new to this, it might take at least 30 mins if you go real slow and being careful about it.
This is considered a Hack, for those of us who cannot or do not want to pay much money to fix our car.
If you are able to afford $500 or $1000 just to replace this particular part, be my guest.

Here I am showing this for information only.


Proceed at your own risk and peril, please take safety precautions.
I am NOT responsible, nor liable for any personal safety, product failure arising from you attempting this job yourself.

Do not blame me for your mistakes and errors, you are fully responsible of your actions.

Common tool needed:
Chisel
Hammer
seesaw or drumel
cleaning towel
sealing silicon
The new replacement Cap can be found on Amazon: "Cheriezing 11127570292 Engine Valve Cover for BMW X1 X3 X5 X6 xDrive 535i 335i 435i"

Based on my observation:
You do need much glue to fix it, at least with the N55.
You dont need to over-glue this replacement cap... just enough for it to hold.



1) you start by cutting one of the corner of cap at the top, without going too deep.... you should stop as soon as you see the orange membrane:



It's plastic, so this is going to go real fast...

This is what you are trying to do: cut as carefully as possible one side of the cap so that it can be popped up/open...


The PCV/CCP Cap is essentially snapped/clipped to the top of the engine cover, contrarily to what most people thing... and even if it was glue, it was done very very lightly...

The reason is, under normal operation and load, the CAP is Sucked tight... the pressure is negative: meaning that the vacuum from the engine maintains the cap in place by suction.

2) When you start seeing the orange membrane, proceed very carefully, so that you do not damage the Engine Cover:



3) You want to cut the cap and achieve this:

Once you arrive at this stage, you should take a thin phillips screw driver to pry this cap open as carefully as possible:



4) You can either pry the side of the cap or if there is a gap at the top going above the orange seal as i did here:


a bit savage:



5) Clean Snap up!


The reason there is a spring under the cap is because the spring prevents the orange plastic membrane from collapsing due to the engine vacuum suction...

The membrane serves as a soft sealing cap that can allow pressure differential, and the black plastic cap is to protect that soft membrane from the elements.

6) Analysis of the damage and failure:

The way you open and remove this cap from the Engine Valves Cover is destructive, you will not be able to re-use it because it already has failed in the first place...

In this photo you will see the damage i did to the cap, but also the cracks on the orange membrane that could not have been induced by me or during the removal... The orange membrane already failed and cracked prior to our removal.





I destroyed the side of the black cap, but the orange membrane shown here is clearly cracked prior to my removal... due to constant suction over 7 years... (hold you jokes guys)







7) CLean up the blow-by engine oil that has been caked/baked here:



8) The replacement part doesn't look the same, but it fits in perfectly:


This is how it would fit in, as oriented:


9) you dont have to clean, but it is the right thing to do at this point:


10) from this perspective, you can see the small little damage i did to the engine cover when i was trying to cut the PCV cap:


Try to avoid cutting the Engine Cover/Housing for the PCV/CCV Cap like i did:


11) Once all cleaned up, do not forget to put back the spring:



12) Notice the light gray line around the outside wall of the "cylinder":

That's the very little amount of "glue" originally used to seal it...

so that's how little we are going to try to use:


13) you can just smear just a little bit of plumbing/silicon gasket/sealer around the side of the cap, to prevent tiny air leak into the engine...

DO NOT PUT glue or sealant on the top surface, only on the side outside wall, do not put inside the cap


The reason you dont want to use too much of is: so that you can be able to do this job about 70,000 miles later down the road...:

if you use superglue, or too much sealant, then it will be impossible for you to remove the cap again...


14) Snap or push the Cap down in the correct orientation.



Hold it down for a couple of minutes so that the cap doesn't spring back out, help the glue or sealant cure and set before letting go





IMPORTANT: There is a tiny plastic cap at the top of the PCV cap you are replacing, you need to remove it and put it on the new replacement PCV Cap!





Good Luck... and remember, i am not responsible for your screw ups.



You can find a lot of youtube videos on this topic, but most of them are showing how to do this the long tedious way.

For the N55, it is very simple for 2 reasons:
1) The PCV/CCV location is right on the top, ease of access, but Depending on your engine type, it can be in weird places where you have to remove quite a bit of things and potentially even the Engine Valves Cover.
2) There is no retaining tabs/clips to break off, as could be seen on much older engine model/types. On the N55, the PCV is flat at the top, so the cap doesn't risk to fall off. On other engine, it might be off to the side of the engine, at an angled surface, which would require the use of glue...

I have to give credit where credit is due:

Thanks mate for this tip!

[Pussiwillow]

New to n55 platform, so pardon my lack of knowledge, when people do a valve cover gasket job, they recommend replacement of the valve cover as well, is the failed cap the reason they do so? More of a hey were this far and they fail at xx miles on average etc, so this fix would allow you to reuse the valve cover (if that's the reason for replacement)
Sorry haven't looked into it since mines not leaking so figured I'd ask

[DrivenByE30]

Originally Posted by Pussiwillow

New to n55 platform, so pardon my lack of knowledge, when people do a valve cover gasket job, they recommend replacement of the valve cover as well, is the failed cap the reason they do so? More of a hey were this far and they fail at xx miles on average etc, so this fix would allow you to reuse the valve cover (if that's the reason for replacement)
Sorry haven't looked into it since mines not leaking so figured I'd ask

It depends on a lot of factors/variables/mileage and what your situation is:

This PCV Cap never failed for me since new, until now (failed at around 98,000 miles).
My Engine Valves Cover is still in very good condition, and there is no reason for me to spend over $350 to replace it, especially if it's only for the PCV Cap.

I suspect it is the same case for most people too, but unfortunately Most people will go through changing, as you pointed it out:
1) Engine Valve Cover, which has integrated to it:
2) new PCV Cap
2) and Valves Cover Gasket, because you removed the Engine Valve Cover...

You are essentially paying for much more than you need to, if you go with the dealership... i dont know why they wouldn't do this way...

i suspect this job doesn't feed their family enough... but most people dont know what...

Second scenario
If you have a job that requires you to remove the engine cover (as in your case of replacing the gasket), then yes, you will have no choice but to replace all the above as a convenience (depending again on your mileage, if you think the PCV cap will fail soon...)


Third scenario is:
Let's assume you remove the engine cover for whatever reason, and replaced the gasket, fix whatever problem on the engine and put everything back together without replaceing the engine cover (because most of the time you only need to replace the gasket but not the cover), then a few thousand miles later, this PCV failure occurs, well you can either replace the whole cover or did what i did, and still keep both gasket and engine cover...

I hope my explanation wasn't too confusing...


EDIT:
I originally replaced my valve cover gaskets @ 60,000 miles because it was leaking oil... but i had kept the engine cover intact (as well as the PCV). I only paid for the gaskets then.
now pratically @ 100,000, the PCV cap failed and i really didn't want to spend over $350 to replace my engine cover which is perfectly fine, so i only spend $15 to replace that PCV cap
that way i dont have to replace the gaskets again for no reason...


EDIT 2:
Even if you replace your valve cover gaskets, and remove the engine valve cover, and wanted to replace the PCV cap, i would still advice you to do the above... there is no reason to replace the entire engine valve cover, because that thing will never fail, unless it is badly clogged, but that would mean you have much bigger issues...

[Pussiwillow]

Perfect that's exactly what I was looking for, thank you sir!

[F32Fleet]

Originally Posted by Pussiwillow

New to n55 platform, so pardon my lack of knowledge, when people do a valve cover gasket job, they recommend replacement of the valve cover as well, is the failed cap the reason they do so? More of a hey were this far and they fail at xx miles on average etc, so this fix would allow you to reuse the valve cover (if that's the reason for replacement)
Sorry haven't looked into it since mines not leaking so figured I'd ask

Ya that's part of it. In addition, depending on the mileage, the VC can have shrunk a little which will reduce the service life of the gasket repair. I personally didn't like the idea of this particular hack repair so I opted to replace my VC when I did the gasket (55k miles).

If I was under 50k miles I'd reuse the cover.

[Bowenpuref3p]

Originally Posted by F32Fleet

Ya that's part of it. In addition, depending on the mileage, the VC can have shrunk a little which will reduce the service life of the gasket repair. I personally didn't like the idea of this particular hack repair so I opted to replace my VC when I did the gasket (55k miles).

If I was under 50k miles I'd reuse the cover.

Where can you buy just the cap? I did a quick search and only found one place and the site is ghetto and sketchy looking.

[DrivenByE30]

Originally Posted by Bowenpuref3p

Where can you buy just the cap? I did a quick search and only found one place and the site is ghetto and sketchy looking.

This is the one i bought on Amazon:
Cheriezing 11127570292 Engine Valve Cover for BMW X1 X3 X5 X6 xDrive 535i 335i 435i

i will update my original post to include the reference.

[Bowenpuref3p]

Originally Posted by DrivenByE30

This is the one i bought on Amazon:
Cheriezing 11127570292 Engine Valve Cover for BMW X1 X3 X5 X6 xDrive 535i 335i 435i

i will update my original post to include the reference.

Ok cool. my pcv system is fine at the moment just wanted to make a note for the future. Thanks

[marcoxtv]

Originally Posted by DrivenByE30

My car is a 2012 F30 335i (N55), it has about 99,300 miles.

After 7-8 years, the PCV/CCV on these cars will usually fail.



The failure is due to the thin orange plastic membrane under the PCV/CCV cap, which is at the top of the Engine Valves Cover.

PCV = Pressure Crankcase Valve
CCV = Crank Case Valve



The symptom to this failure is usually either:
- hissing noise at the top of the engine due to the air being sucked into
- idling of the engine is irregular, and sometimes engine would shut down, similar to as if you had left the oil cap slightly loose or not fully tighten...

The purpose of this membrane is to maintain a sealed vacuum within the engine, and yet to allow the pressure to change without damaging engine components.

A crack membrane (failure over time) compromises the vacuum of the engine, and thus the engine will have difficulty working.

The normal way to fix this is to have the entire Engine Valves Cover replaced, which can cost anywhere between $170 to excess of $500 depending on which brand, official or knock-off you buy, and labor at the dealership can vary between 2hours up to 5hours ($200 to excess of $500).



For $15, you can fix it yourself, this job is only 5 to 10 mins long, but if you are new to this, it might take at least 30 mins if you go real slow and being careful about it.
This is considered a Hack, for those of us who cannot or do not want to pay much money to fix our car.
If you are able to afford $500 or $1000 just to replace this particular part, be my guest.

Here I am showing this for information only.


Proceed at your own risk and peril, please take safety precautions.
I am NOT responsible, nor liable for any personal safety, product failure arising from you attempting this job yourself.

Do not blame me for your mistakes and errors, you are fully responsible of your actions.

Common tool needed:
Chisel
Hammer
seesaw or drumel
cleaning towel
sealing silicon
The new replacement Cap can be found on Amazon: "Cheriezing 11127570292 Engine Valve Cover for BMW X1 X3 X5 X6 xDrive 535i 335i 435i"

Based on my observation:
You do need much glue to fix it, at least with the N55.
You dont need to over-glue this replacement cap... just enough for it to hold.



1) you start by cutting one of the corner of cap at the top, without going too deep.... you should stop as soon as you see the orange membrane:



It's plastic, so this is going to go real fast...

This is what you are trying to do: cut as carefully as possible one side of the cap so that it can be popped up/open...


The PCV/CCP Cap is essentially snapped/clipped to the top of the engine cover, contrarily to what most people thing... and even if it was glue, it was done very very lightly...

The reason is, under normal operation and load, the CAP is Sucked tight... the pressure is negative: meaning that the vacuum from the engine maintains the cap in place by suction.

2) When you start seeing the orange membrane, proceed very carefully, so that you do not damage the Engine Cover:



3) You want to cut the cap and achieve this:

Once you arrive at this stage, you should take a thin phillips screw driver to pry this cap open as carefully as possible:



4) You can either pry the side of the cap or if there is a gap at the top going above the orange seal as i did here:


a bit savage:



5) Clean Snap up!


The reason there is a spring under the cap is because the spring prevents the orange plastic membrane from collapsing due to the engine vacuum suction...

The membrane serves as a soft sealing cap that can allow pressure differential, and the black plastic cap is to protect that soft membrane from the elements.

6) Analysis of the damage and failure:

The way you open and remove this cap from the Engine Valves Cover is destructive, you will not be able to re-use it because it already has failed in the first place...

In this photo you will see the damage i did to the cap, but also the cracks on the orange membrane that could not have been induced by me or during the removal... The orange membrane already failed and cracked prior to our removal.





I destroyed the side of the black cap, but the orange membrane shown here is clearly cracked prior to my removal... due to constant suction over 7 years... (hold you jokes guys)







7) CLean up the blow-by engine oil that has been caked/baked here:



8) The replacement part doesn't look the same, but it fits in perfectly:


This is how it would fit in, as oriented:


9) you dont have to clean, but it is the right thing to do at this point:


10) from this perspective, you can see the small little damage i did to the engine cover when i was trying to cut the PCV cap:


Try to avoid cutting the Engine Cover/Housing for the PCV/CCV Cap like i did:


11) Once all cleaned up, do not forget to put back the spring:



12) Notice the light gray line around the outside wall of the "cylinder":

That's the very little amount of "glue" originally used to seal it...

so that's how little we are going to try to use:


13) you can just smear just a little bit of plumbing/silicon gasket/sealer around the side of the cap, to prevent tiny air leak into the engine...

DO NOT PUT glue or sealant on the top surface, only on the side outside wall, do not put inside the cap


The reason you dont want to use too much of is: so that you can be able to do this job about 70,000 miles later down the road...:

if you use superglue, or too much sealant, then it will be impossible for you to remove the cap again...


14) Snap or push the Cap down in the correct orientation.



Hold it down for a couple of minutes so that the cap doesn't spring back out, help the glue or sealant cure and set before letting go





IMPORTANT: There is a tiny plastic cap at the top of the PCV cap you are replacing, you need to remove it and put it on the new replacement PCV Cap!





Good Luck... and remember, i am not responsible for your screw ups.



You can find a lot of youtube videos on this topic, but most of them are showing how to do this the long tedious way.

For the N55, it is very simple for 2 reasons:
1) The PCV/CCV location is right on the top, ease of access, but Depending on your engine type, it can be in weird places where you have to remove quite a bit of things and potentially even the Engine Valves Cover.
2) There is no retaining tabs/clips to break off, as could be seen on much older engine model/types. On the N55, the PCV is flat at the top, so the cap doesn't risk to fall off. On other engine, it might be off to the side of the engine, at an angled surface, which would require the use of glue...

I have to give credit where credit is due:

Thanks mate for this tip!

I lost the little plastic cap on the top of the valvr can i just leave it like that or im i in trouble?

[kenshirosan]

thank you but are you french ??

[Boost life]

Why cant we just put an aftermarket inline PCV in the pipe that comes out of the PCV?

[Skiy]

One thing nobody mentions is that there there are a total of 3 valves with such orange membranes sealing airflow in various directions. The top circular membrane might be the one to fail first but there also two other ones that open and close which can also get clogged or go bad so it’s recommend to replace whole valve cover to prevent doing this job twice.

[kickthecan]

Originally Posted by Skiy

One thing nobody mentions is that there there are a total of 3 valves with such orange membranes sealing airflow in various directions. The top circular membrane might be the one to fail first but there also two other ones that open and close which can also get clogged or go bad so it’s recommend to replace whole valve cover to prevent doing this job twice.

To be fair, I'd argue OPs method is easier to do...multiple times over vs a whole valve cover replacement if you weren't taking off the valve cover

However, if one was already doing valve cover gaskets, then yeah, I'd just replace the whole cover

[alphawawa]

This may be the best bang for the buck "hack" (meant in the best way possible, as you did) I've ever seen for a BMW repair. Thanks so much for the detailed documentation - great job.

I ended up using a minimal amount of Permatex Ultra Black gasket maker instead of silicone, as I figured there was no doubt that it can withstand the heat cycling involved.

I'll report back here if this hack fails in any way. Fingers crossed.

UPDATE 1: This seemed to work for about 25 miles of driving, but then the squealing sound returned during auto start/stops. I used the smoke test to see if the newly placed cap had a new tear, but it seems to be working just fine, so further diagnosis pending.

UPDATE 2: Since it was relatively easy, I decided to remove the cap and use a good ole' German high temp silicon sealer from Victor Reinz. This solution lasted less than 5 miles of driving even though the smoke test again revealed that there was no sucking occurring at the cap, as the squealing returned again (only during Auto Start/Stop Shutdown)

UPDATE 3: Finally succumbed to trying high temp JB Weld for plastic on the cap, and the squealing remained. Ended up paying a local indie shop to replace the cylinder head cover with an OEM unit. So far, no squealing, and no indicated leaks from the front or back main seals either, so not clear what issue was fixed. Maybe the spring constant of the Amazon CPV is different than that of the OEM-integrated one? Someone else indicated there were other similar pressure-adjusting features of the cylinder head cover, but I could not find any on the OEM cover.

CONCLUSION: This was an easy and inexpensive attempted fix but did not resolve the squealing during Auto Start/Stop shutdown.

[richard335i]

Did
You have any rod knock like noise from the vacuum pump do to this valve failure?

[DrivenByE30]

Quick update:
my car is about 110,000 miles and this fix seems to be working fine for me, as i have NO further observations in the past 10,000 miles in regards to the PCV... hopefully i dont jinx myself here.

I also realize that i forgot to mention: after sealing the cap, i would honestly put a brick or something about a pound or 2 (2 or 4 kg) on the top of the cap, in order to help seal and cure it OVERnight.

Originally Posted by richard335i

Did
You have any rod knock like noise from the vacuum pump do to this valve failure?

personally i didn't notice that...

Originally Posted by kenshirosan

thank you but are you french ??

Yes i am.

[ViewsOfTheVI]

Sorry to bring back such an old thread but i was wondering if anyone did this to cure the squealing noise from their car and how long this fix lasted, saw a video where someone replaced just the pcv valve and reduced the squealing from his motor but it didn’t completely go away. Anyone have a long term review of this?

[1004ron]

DrivenByE30
Thanks for the great write-up.

After installation of the 3rd party crankcase pressure regulating valve the crankcase seems to be quite negative at engine idle.

What's the best way to assess the function of this regulating valve?