Hissing from BOV @ idle?

[4G63dsmpwr]

Well when I was in the engine bay the other day, with the car running I noticed that there was a relatively loud hissing coming from the BOV. The car is vented, but it never stalls, I have an AFC, not sure if that helps or not, but it seems to run pretty well.

At idle though, there is constant air coming out of the 3/4" end, and if I put my hand over the end, the idle actually picks up a little bit. Do all stock 1G BOVs do this at idle when vented?

I'm also having some tuning issues, and was wondering what effects, if any this would have on my car. Thanks very much for the help.

 

[Lordpaxin]

the main problem with venting stock bov's is that most leak at idle.

your vacuum system should be totally air tight. if its leaking a little at idle, its leaking even more at boost.

recirculate it again, and see if you can tune it better, see if its faster.

 

[4G63dsmpwr]

Alright thanks for the help. I'm gonna recirc it, and see if it runs better. Thanks for the help!

 

[Coldandafraid]

the main problem with venting stock bov's is that most leak at idle.

your vacuum system should be totally air tight. if its leaking a little at idle, its leaking even more at boost.

recirculate it again, and see if you can tune it better, see if its faster.

Actually, not exactly true. A BOV leaks at idle because the vacuum sucks up on the diaphram and opens the BOV. But under boost, the psi pushes down on the diaphram and closes the bov.

So, its the spring that actaully holds the bov closed at idle, so your spring is weaker than your vacuum.

p.s. you say air coming OUT the bov at idle? If your engine is running with vacuum, air should be getting drawn IN, not out.

 

[Lordpaxin]

WHATEVA!!!!!!

its still bad!!!!!!