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Hey guys,

Recently I just did a +t conversion on my RB25 and I used a stock BOV. It's working great, but I'm just having some issue (or maybe not??) with my BOV. Everytime I press the clutch down, my car's revs goes way down past the idling rev before jumping back up to the idling rev. To me, this seems more like something you would experience with an atmo BOV since the air is not in a closed-loop, but mine is plumbed back. Since I don't know how a "working" stock BOV is supposed to feel on a DEt, I just wanted to know if this was normal, or whether I have a vacuum leak or a stuffed BOV.

Any info would be much appreciated. Thanks guys!

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Is your return modified? If so it might be to big. Might be a leak or you need a tune. Im guessing you have changed your ECU and tuned it?

Yeh, I T-pieced into one of the vacuum line going from the plenum to the charcoal canister. Is that a problem? I did use the larger of the two lines, so you might be right, it might be too big.

I am running pfc and it already had a tune.

or some of the returned air is blowing backwards through your afm. is the return line pointed towards the turbo or a good distance from the afm?

Well that's the thing, I am hearing A LOT of air going out of the system (like an atmo BOV), and I'm assuming passing through the afm, even though it's plumbed back. But like I said, since I don't know what it's supposed to sound like, I simply just assumed that because I was using a pod, it was natural for it to sound like that.

Thanks for the info guys. I'll give these tips a go and hopefully it'll fix the problem.

Edited by mjscar
I am running pfc and it already had a tune.

I would say that's your issue there. If you don't have vacuum leaks etc then I would say it's something to do with the idle setting of the tune. On some occasions my R33 GTST doesn't like to idle. I can be when it's restarted after being warm. Eg idling fine when you pull in to get fuel and then start it up to leave and it starts to carry on. Sometimes get the same when the lights are all on, windscreen wipers and AC too etc I'd be asking your tuner to see if he can fix it.

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