I was adjusting my Blitz DD BOV last night, and I took off the recirculating hose. With the car running, I noticed that there was a vacuum on the outlet tube of the BOV. The BOV still works, but when it's not venting, it's sucking in air. This doesn't seem right to me. Is my BOV bad?

TIA

Leave that outlet hose off and adjust the valve till it stops leaking. It's probably leaking because you have the valve adjusted too soft. Try that and see.
Travis E.

that is normal behavior! leave it alone

andris

mine stock bb one does that.Its normal

I don't think it's adjusted too soft. The whole reason I started adjusting it was because it was too stiff. The BOV kind of sounded like psh-psh-psh-pshhhhhhh which I attributed to a pressure surge when I closed the throttle. I noticed the vacuum before I loosened things up.

If the vacuum is normal, then this is really a HUGE reason to recirculate the BOV. Otherwise it would be sucking in unmetered air the whole time the car is running. Can someone explain in more detail?

ttt

I thought the stock ones would do that, but the aftermarkets weren't supposed too? I guess I'd better start learning some more before I attempt my swap.
Travis E

BOV run off of pressure and Vacuum, it's normal for them to suck air in on idle.

Wouldnt it cause some sort of diffrence since its unmetered air?


Khem

Exactly, Khem. This just seems wrong to me. Can someone explain why it works this way?

Ill ask a friend if his Type S does the same thing today.



Khem

Originally posted by SE-R_Dan
If the vacuum is normal, then this is really a HUGE reason to recirculate the BOV. Otherwise it would be sucking in unmetered air the whole time the car is running. Can someone explain in more detail?


ttt