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PCV hose, delete.

117K views 59 replies 33 participants last post by  Lö-Razor 
#1 · (Edited by Moderator)
Now i'm sure most if not all of you are aware of the issue attaining to the N14 engine, which has the issue of excessive carbon build up on the inlet valves ?

The usual method is to fit an oil catch can or use a cleaning additive such as Seafoam, BG K44 etc etc or maybe both, there has been discussions and I have mentioned this too, about the fitment of water/meth injection to help remove and control the excessive carbon build up.

For a while now I have been testing another solution, and this is to completely remove the rear PCV hose, which feeds the crankcase gas oil mist residue directly into the base of the inlet manifold, which in turn is pulled up into the incoming air flow and finds itself being burnt onto the inlet valves.

So the following photo's show what I have done as another alternative to combat this issue.













And all is well and good.
 
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#2 ·
NOOOOO!!!! I hope I am wrong and I have misunderstood what you have just done but have you completely blanked of the PCV valve?

If you did then why? PCV valve is important. You cannot blank it off. The engine needs to breathe through it to let blow by gasses escape. If you blanked it off then you are going to kill your engine in the next day or two.
 
#7 ·
What would you like to know ?

Probably where to get the blanking caps ?

If that's what you'd like to know, all you have to do, is get yourself to your local Peugeot dealer, and ask them, for 2 Blanking caps, part No: 0361.S4
 
#9 ·
Czar,

How does this work? How does the engine vent the crankcase gases if the outlet is blanked off?
Does the Peugeot blank piece still allow the pressure to be released?
Why do Peugeot produce these blanking pieces?

I had a minor intermittent misfire which the dealer attempted tp sort by replacing the plugs - apparently a bit burnt? Updating the anti-knock software and finally some sort of fuel additive? Also repeatedly advised that I was using 'bad' fuel. At the last visit the senior mechanic told me that he had done some long term comparisons on his own car and only used the main fuel brands - just the normal octane - not the super. Have followed his advice for six month - no misfire! Still worried about the 'coking' due to the direct injection and the breather return issue so interested in this solution?

Cheers

NeilB
 
#11 ·
Czar,

How does this work? How does the engine vent the crankcase gases if the outlet is blanked off? It has a second PCV outlet, into the air intake tube!
Does the Peugeot blank piece still allow the pressure to be released? Yes it vents through the second PCV outlet.
Why do Peugeot produce these blanking pieces? Peugeot do not produce these caps, they are produced by, Norma fittings, and commonly used by many different manufacturers.

I had a minor intermittent misfire which the dealer attempted tp sort by replacing the plugs - apparently a bit burnt? Updating the anti-knock software and finally some sort of fuel additive? Also repeatedly advised that I was using 'bad' fuel. At the last visit the senior mechanic told me that he had done some long term comparisons on his own car and only used the main fuel brands - just the normal octane - not the super. Have followed his advice for six month - no misfire! Still worried about the 'coking' due to the direct injection and the breather return issue so interested in this solution?

Cheers

NeilB
Hi
Thanks for your reply, I am just trying to get my head round what i can do to look after my car, all i keep reading everywhere is that there are numerous problems with this engine.
I found a link about this PCV delete because i noticed that some people had stated that it was related to knock sensor codes which i have had to have taken off once at the dealer.
How long have you been running this mod ? Over a year, with no problems.
does it have any other effects ? Blanking off the rear PCV, reduces the direct contaminated flow, of the crankcase oil mist residue gasses, and helps in controlling/reducing the carbon build up, on the backs of the inlet valves.
I have also had to change the sump gasket on my car and read somewhere that it can aslo be connected to crankcase pressure ? Crankcase pressure can be responsible for gaskets/seals leaking, that said, the amount of crankcase pressure varies, from engine to engine, manufacturer to manufacturer.

Ian
.
 
#17 ·
Hello Czar.

Trying to cope with the carbon buildup problem i found that blanking the pcv as you described is the best -so far- solution.
I have already bought the caps from Peugeot and a BSH Oil Catch Can.
But what about the pressure that is developing in the crankcase? Can it cause gasket/seals leaking?
Original questions posed by "goosejc00" and "Neil B Scot" but seems like i cannot find you answer...
And what about the "front vetilation pipe" on the top of the engine that ends up into the turbo inlet?
Is it to lubricate the turbo somehow?
I am thinking of blanking that too.

Thank you for your time and help!
 
#18 ·
Each individual engine, produces varying amounts of crankcase pressure, that said, blanking off the rear PCV will not effect your engines ability to evacuate the crankcase gas, this will now be vented through the one remaining front PCV, which feeds directly into the air intake, for the turbo, it is NOT there to lubricate the turbo, nor is it a good idea to close this off!

If you do have both PCV lines closed, then you will find your engine will find the weakest point to vent, the crankcase gas pressure, creating a huge problem for you and your engine!
 
#19 ·
Czar thank you for your prompt response and for sharing your knowledge with us!

I think i have figured out what you're saying and it really does make sense.
In any case the "back" PCV will be deleted, meaning blocked.
One last question concerning the front and i'm off to materialize my setup:
What if instead of routing it through an oil catch can (i have already bought a BSH) into the turbo inlet i just "terminate" it with a K&N Crankcase Vent Filter (i'm not allowed yet to post URLs to other sites due to less than 15 posts) and just tap the turbo inlet hole saving the turbo and everything attached behind it from the "oily bath".
The K&N Crankcase Vent Filter will allow the engine to breathe without the use of an oil catch can.

Thank you in advance!
 
#20 ·
VTA (venting to atmosphere) will work, however, your crankcase vent filter, will quickly become saturated with oil mist residue, and once saturated, it will deposit an oily mist all over your engine bay, even finding it's way onto the road surface too!

Also, you and your passengers will quickly become fed up, of the burn't oily smell entering your MINI, i advise you to forget about VTA.
 
#21 ·
Czar thank you very much once again!
You've been most helpful.

As per my conclusion the safest (cleanest) solution for the engine's reliability in the long run is the VTA apart -fo course- of the problems you pointed out wisely.

Second best is attaching an oil catch can that really works (any suggestions although i've ordered a BSH are welcome).

In anyway the blocking of rear PCV is a one way solution.

Kind regards
 
#22 ·
Hey Czar,

This may be a dumb question, but why do you recommend deleting the passenger side PCV with an OCC on the driver side rather than the other way around. If they crankcase vapors aren't there to lubricate the turbo, then isn't it better to close off the driver's side to prevent all that junk from collecting the in IC or gumming up the turbo?
 
#23 ·
You've almost answered your own question!

The passenger side PCV has the shortest direct route to carry the hot oil mist residue to the back of the inlet valves, that said, this PCV only opens during idle and off boost throttle situations, so most of the time for those who drive gently!

The drivers side PCV only operates (opens) when the vacuum pressure differential from the turbo (boost) is greater than the vacuum pressure draw from the inlet manifold, so therefore it is much more beneficial to cap off the passenger side PCV and put the OCC on the drivers side PCV line!
 
#27 ·
Hey Guys,

Does anyone knows if 2009 fJCW has the external pressure release valve. Infact I do own a 2009 fJCW and has not noticed that it has the external pressure release valve. I have installed the two caps and took the vacumm hose out totally. The vacumm hose has loads of oils in it. I am very glad that all these oil not making their way into my engine.

Immediately the capping of the two opening, i took a long 800km journey with average speed of 160km/h,at times reaching 200km/h on motorway. So far so good.
I have not noticed anything wrong at all.

Next will be in the look out for OCC.

Hi Czar, you want to send your OCC to Malaysia?
 
#29 ·
My 2010 Countryman suffers from a massive loss of power at times when accelerating hard, I suspect that it is this PCV problem, it's been back to the dealer 3 times and I've had the usual 'no fault code, no problem' each time.

It cannot be reproduced at will, although has happened a few times in exactly the same circumstances, driving slowly on closed or part throttle downhill at around 40mph for maybe half a mile and then dropping a couple of gears and flooring it. I often try and reproduce the problem as I use that bit of road every day but it has been elusive recently.

Is there a definitive way of reproducing the problem to demonstrate it to the dealer?

Thanks.
 
#38 ·
pcv plugs

i fitted these blanking plugs on 09 mcs, on start up i get a smell of oil think this is coming from vent on rocker anyone else noticed this?
These are now fitted as standard to rcz 207 ds 3 models fitted with this engine, instead of redesigning rocker and manifold so pug/cit are addressing this issue but mini are blind to the problem, have spoke to tech after tech at bmw and there s no problem?:(
 
#39 ·
I have done the delete to my 57 MCS & get the smell when stationary just after starting the engine & when i'm outside after a run. The inside smell goes away very quickly when i get moving.

---
Tab

i fitted these blanking plugs on 09 mcs, on start up i get a smell of oil think this is coming from vent on rocker anyone else noticed this?
These are now fitted as standard to rcz 207 ds 3 models fitted with this engine, instead of redesigning rocker and manifold so pug/cit are addressing this issue but mini are blind to the problem, have spoke to tech after tech at bmw and there s no problem?:(
 
#42 ·
Sorry to thread hijack guys.

MY N14 CS had its PCV tube disconnected when I bought it..................I reconnected it and now from the valve cover it hisses on the left hand side......I am thinking that the Valve itself is dead. Are these quite easy to replace? I havent got the bentley through yet so do not know where it is located.


Thanks
 
#43 ·
Hello, i'm new to this, i have a 2009 mcs with an old engine (pre-dec 08). I'm thinking to use this caps but its very controversial on the internet and nothing is recent. Any of you guys still using this solution?

I don't have occ btw, stock setup with superknock and high oil consumption.
 
#46 ·
Hi,

I believe one of the guys asked the question, I have been wondering but there is no answer. (Unless my dumb butt missed it). Instead of deleting the PCV hose on left side could one just add a Catch can to prevent oil from entering the intake thus preventing build up?
 
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