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Old 11-16-2011, 10:57 AM
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bricas45 bricas45 is online now
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Location: Virginia
Join Date: Jan 2009
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Mein Auto: 335i, 540i6, X5
Originally Posted by 540alex View Post
I haven't got a chance to smoke test it yet. Before I tested from the SC inlet. BOV is a possibility, but I don't believe it has a big leak at least when the engine is off and I'm not sure how to properly tune it. It does leak a little bit past the adjustment screw though, but I don't think it's major. What I really want to do is try my "new" Bosch BOV, but I have to find reducers that will work with it. It has both sides at 25mm diameter (roughly 1"), one side needs to connect with a straight reducer to 45mm pipe (1 3/4") and the other needs a 90 degree elbow reducer to 39mm (1 1/2"). The elbow should not be a problem, but the straight ones I see online are all 3" to 4" long and what it needs is about 7". I want to avoid any additional adapters, so not sure yet what/where to find this thing. Any idea?

Those torx bolts are something else indeed. I had fun time trying to tighten the one in the bottom left corner. I also thought of replacing mine with a hex head, but I if I remember correctly, it gave me an impression that the space is too tight for it.

I know what you mean by a can of worms That's a big part of why it took me months to get it back together and I'm still at it It now makes sense why your mechanic would call you and tell you there is a number of other things wrong with your car besides the one you actually brought it in to have fixed. They weren't kidding!
Not sure about connecting the Bosch valve that is the one VF and ESS use on their kits. It very well could be that your BOV is tuned to open at ~3psi and you may not have a vacuum leak at all. I would try playing with the settings. Tune to one extreme look at pressure WOT, tune other way, and step up. I think mine came with a tuning process.

Can you take adjustment screw off and use Teflon tape on threads?

Again run leak test directly into throttle body to eliminate SC system. And then start attaching parts and make your way to filter. I think starting with filter is just too many variables. Or if you want to just test the SC system cap the inlet to throttle body and pressurize from filter. Maybe even plug off the connections to the BOV.
2013 - X5 35D
2009 - 335i coupe FBO
2001 - SC 540i
1986 - 318i Turbo
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