Bov Backwards

[yw84u]

I was doing some work on my engine today and I noticed that it looked like my BOV was one the wrong way. My car has always fluttered very loud on backoff and I just put this down to my cold air intake. So I took it all apart and what I found suprised me. The tube that connects next to the throttle body was not connected to the outlet opposite to the vacuum hose but to the outlet on the side of the BOV and the outlet opposite to where the vacuum hose connects was connected to the inlet tract. I could not work out how the BOV could possibly work like this so I switched it around and blocked off the outlet on the inlet tract. It now makes the sound a BOV should with 1 big woosh. I have not touched the BOV before. Has anyone else noticed this before?

This is how the BOV is now

this is what it now sounds like. the woosh is alot louder than it seems in the video

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Edited 10/11/07 12:57 PM by yw84u

[Ralph Wiggum]

Bosch OEM bov's all have the Inlet on the side and the vent in the middle. Opposite to a after market bov. Dont be surprised if you bov leaks boost the way you have it set up now. They are designed this way to allow them to operate correctly at low boost levels The seat spring in a stock bosch bov is very light and the decreased surface area that the pressurized air acts on by entering in the side allows this to work. You have increase the surface are by about 200% so it likely the bov is bleeding off boost now.

[yw84u]

ow ok so that is how it is supposed to be. I just seemed weird how it was positioned and I couldn't see how it would work like that as all BOV I have seen before are positioned like I changed it to. thanks for that