Possible bad DV? Flutter?

[helldiver14]

APR Stage 2 08 FSI with straight pipe, forge blow off and Forge twin take. Anyways, when accelerating in the upper rpm's and letting off I have noticed that I have a flutter sound and around 4750 RPM I can feel my boost dropping off. I'm not sure if the previous owner had replaced the DV with an aftermarket, but after reading it sounds like whatever one is in there isn't holding boost past the 4750. Any thoughts or is this just normal sound for a Stage 2?

 

[Jyuen]

Well you literally listed a forge BOV.. that would be the direct part that replaces the DV.

You say you accelerate and let off, are you flooring it to 4750 and lifting off the gas pedal? If so, that's normal boost venting through the blow off valve as you release throttle.

If your flooring it and you lose all your boost at 4750 with it still floored then you have a boost leak and you'll need to find the source.

 

[helldiver14]

Sorry, meant forge spacer blow off.

 

[Jyuen]

So are you letting off the gas @4750 or is the boost venting on its own @4750 with your foot still on the gas?