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Hi,

I know this seems to be a hot topic, and I have done a quick search, but I still havnt found the information/answer im looking for.

Now the motor has done 225ks although it is tired and is slowly losing power, it still performs. I currently only have a fmic, cai, tbe and thats about it in terms of power, but ran a 171rwkw a while ago with these mods.

I have blocked the Red bits, and the blue bits are vented to the atmosphere.

post-37206-1289551906_thumb.jpg

Some people frown upon it, and some say its fine, all i know it seems to be working well, although i have noticed that it seems to stall when it decelerates rapidly eg. when pulling up to lights with my foot on the clutch and hard breaking. This is not the case when i return it back to the factory set up.

My main concern is this;

I'm currently not running a BOV, and would like to return it back to the standard set up to get rid of this stalling problem, but also just because im sure Nissan engineers are smarter then i am in this field regardless of what people think about emissions, a vacuum to get rid of crankcase pressure is better then the atmospheric pressure.

Would running the standard PCV setup without a BOV mean that the "flutter"/back pressure created pressurise the crankcase and put me in a worse situation?

Thank you.

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noticed the brake booster location.. your car's left hand drive?

i do realise that my car will also near-stall if i block the blow off too, however i don't think the bov has anything to do with crank case pressure because its just a valve that regulates the air in the pre-throttle pipes when the throttle is shut

Edited by chiksluvit
noticed the brake booster location.. your car's left hand drive?

i do realise that my car will also near-stall if i block the blow off too, however i don't think the bov has anything to do with crank case pressure because its just a valve that regulates the air in the pre-throttle pipes when the throttle is shut

Oh sorry i should have noted, that the pic of the RB is just one i found on the internet, i just used it to demonstrate how mine is set up.

It's not the blocking of the blow off valve that makes it near stall, its when it's set up like the above picture (PCV Setup) it does that.

The reason i ask if not having a BOV affects this, is because i understand the back pressure/surge coming back through the intake pipe will lead the air back to the head, which might damage the motor, thats what i need to clarify.

Thanks.

should be sweet like that . pos bov is causing it . needs to be plumb back . or adjust the tension on the spring till you get it to work . in my opinion those bov are rubbish and could never get it to work satisfactory

should be sweet like that . pos bov is causing it . needs to be plumb back . or adjust the tension on the spring till you get it to work . in my opinion those bov are rubbish and could never get it to work satisfactory

The picture above isn't one of my engine bay, its just one i found on the net to show how i've got the PCV plumbing set up.

Currently not running a bov.

Thanks.

I had th4e same problem when i installed a blitz BOV (Bought used). Messed around with the spring tension and it wasnt stalling anymore. But i noticed better response from the engine with the stock recirculating valve, so i changed back to stock.

Its not the PCV/Breather setup causing the stalling, its the fact you have removed/blocked the factory BOV, reconnect it and it will fix the stalling problem. Had same issue with my S15...blocked factory BOV for hectik flutters, got over it within a few weeks and unblocked it, car drove perfect on part throttle etc, no stalling, surging etc...

Edited by NSNPWR
Its not the PCV/Breather setup causing the stalling, its the fact you have removed/blocked the factory BOV, reconnect it and it will fix the stalling problem. Had same issue with my S15...blocked factory BOV for hectik flutters, got over it within a few weeks and unblocked it, car drove perfect on part throttle etc, no stalling, surging etc...

When I connect the PCV plumbing how it came from stock, i lose the stalling issue.

But the stalling issue isnt my concern, my concern is running the standard PCV pluming with flutter, will this cause damage?

Thanks.

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