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I have been mucking around with the BOV and now it sounds like ****!.

Im not sure on wether to tighten it or loosen it, If its to tight then it wont release the boost until its too high and too loose it will lose preasure.

It used to sounds really good but now :D it sounds crap now, wish i never touched it but curiosity got the best me.

Any ideas please how to get it hissing pssssstttt nicely once again

thanks

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Last night comnig home from work, I couldnt stand it anymore so i pulled the BOV off and pulled it all apart.

It was really dirty so i cleaned it all up oiled it and put it back and noticed that the pipe that runs from the BOV to the Bleed valve was torn where it connects to the BOV so i cut it and put back on.

!!!!!!AND IT WORKS!!!!!!!!

:lol:

The problem seems to have been the torn pipe but after the cleaning and oiling of the BOV it sounds better.

Have to see if it stalls now, hopefully not

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Its a very common problem with Atmo B.O.V's

When the inducted air is taken in the Air Flow Meter reads the amount and adjusts the fuel delivery to suit that amount of air. The BOV releases the same air that the air flow meter "thinks" has been mixed with the fuel.

So basically the computer injects the fuel but the air has vented out of the BOV, which causes the engine to "run rich". When the mix isn't right and its too rich the engine stalls.

Like the factory unit, a "plumb-back BOV" recirculates the air back into the system, thus equalizing the air/fuel ratios again.

Apart from the sound there is no clear advantge that i know about from having a Atmo BOV. Probably disadvantge.

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RPM

i have the turbo smart plumb back BOV and it still has the stalling problem. i read some of the other posts in the forums and their seems to be a couple of theries and a few sollutions. one way i tryed was to adjust the idle. it seems to work but now she idles @ about 900rpm. is this too high for idle? can this cause any damage to motor? fuel economy dosent seem to be affected too much can still get around 400 k's a tank.

Also before i adjusted the idle it seemed to be very lumpy. having a range of about 500 - 750rpm. Is this common in early model lines? (i have a R32 GTST) i have heard that this can be caused by a damaged or faulty AFM.

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Listen, There's heaps more people on these forums who know a ****load more then I. But I'll give it ago. And I have Noooo problem being corrected by someone who knows better.

The 900rpm Idle should be fine, I think there suupose to idle between 700-900rpm, mine idles at 900 all the time with no problems at all.

The stalling could be a number of things, but since this is a post about BOV's, I'd check all the lines on the BOV and make sure the piston is releasing at a correct pressure...If the spring is rooted which holds the piston closed under boost is weaken it could leak and stall the same way as a Atmo one does.

If the AFM is suspected its something for an expert, as it could cuase the car to run ultra rich or super lean, the later being the worse, as lean equals an expanding piston and an expanding piston can really screw your day up. That could be going to extremes there....

As for the lumpiness of the RB20DET, not sure, I'm got the RB25DET and the few mechanics I know have always commented how smooth the Nissan Engines are.

I'd check all your spark plugs, ignition,and AFM if shes rough.

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i have the turbo smart plumb back BOV and it still has the stalling problem.

plumb back doesn't work?

bout to trade my Turbosmart type 2 bov for a type 3 cos the guys at CAS says if u incurred problems with stalling, buy a type 3 or other similiar bov.

mine's stalled occasionally now but was stalling heaps after i installed the FMIC, thanks to the Unichip.

mine revved to 1200rpm when starting te car and settled to 900rpm.

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  • 3 weeks later...

The reason why, is called reversion.

What happens is the BOV is alot tighter than the factory one, so when the aftermarket one open it does not let out all the air and some of it passes out through the airfilter.

Before it passes out the airfilter it cools the AFM element down and the computer reads this as the car is using more air and compensates for the amount of fuel going into the engine, hence the engine going into a rich condition for a second.

Doc

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