So I replaced a few parts on the car nothing to major just updated some bolt ons. One was the intake to a JMF. That intake as you know is metal. The BOV I am running is the Greddy RS recirculating since 06'. The issue is now with the new intake I can hear a lot of flutter from the BOV where previously there was none. The flutter occurs all the time when letting off and at speed or WOT a short piercing chirp fowllowed by a slight flutter. I have tried adjusting the stiffness of the spring with no change. Is this just something you can here with the metal intake or do you guys think the BOV is worn out. I didn't wanna shell out an extra couple hundred on a new BOV to get the same result. Let me know what you think.
Thanks

 

chances are you just couldn't hear it before

 

oem evo 9 bov works well. but depends on your boost. i run 25psi on mine without any issues.

 

24psi on pump

 

even if I couldn't hear it, which I agree was most likely the case. Shouldn't there not be that much fluttering? It leads me to believe the valve is not functioning properly.

 

Is your diaphragm pinched and what spring or springs and how is the boost vac line set up

 

do you fell the flutter when you let go off your gas? Do you see your RPM hesitate?

 

I have never disassembled the BOV so I don't know how it would be pinched. It us the stiffer of the two springs that came with it. The Vac line is set up like stock other than the addition of the mbc.

 

Yea make sure the vac line isn't being pinched. Check the actual orientation of the bov, it might be upside down too.

 

I recently went over all the vac lines as I had a leak. Also The BOV is straight up as it should be.

 

put the softer spring in and set the preload as low as it will go

 

The single larger spring aka on a type a "single spring mod " is what I use. Never any flutter

 

the intake makes it sound louder, it may have been fluttering all along

 

I know mine does more work now that my boost is turned up a bit. Definately hear it more. I think its just doing what its supposed to do. I think driving style is a factor. Boost levels .Where your rpm's and throttle are at your shifts. IDK not a guru.

 

Properly set up it should vent at relatively minor delta p.

They're usually over looked in set up for proper function .. idle vacuum should make it light on the seat.and a dedicated reference line are key attributes imho