OEM DV (Diaphragm) Flutter?

[-SnowMan-]

I replaced my OEM Diaphragm DV with a Rev. D that turned out being faulty as well so I out the original back on while I wait for the second new Rev. D.

My original DV will flutter when I come off boost.

My understanding of fluttering is that compression surge will make that sound while ACCELERATING.

This happens when I let off the gas completely.

Is this damaging anything? It seems many people hear fluttering when they have an aftermarket intake.

I have a new DV ordered, just wanted to be sure nothing was problematic for now.

 

[high_octane3541]

Diverting air

 

[nkresho]

As long as it's venting, you should be good. My forge did it on k03, so I switched to a rev d. Still did it. I think it's more noticeable on different intakes with different harmonics.

I even tested the wiring to make sure the dv was getting voltage when it's supposed to open. All good to go.

When I let off slowly, after making boost, it sounds like curly whooping. https://www.youtube.com/watch?v=g5j8Jioan1w

I've gotten used to it. At higher boost it gives the regular psssshhhh, so I know it's working. And, it holds 20 to redline, so it's not leaking on me either.

Mine is not as bad as this, but close: https://www.youtube.com/watch?v=2EdDflM5Osk

It will only make that sound if I let off slow. Quickly letting off the gas will do the pssshh.

 

[Chris@DoubleApex]

My original DV will flutter when I come off boost.

It's possible its not opening. If its working properly it usually makes more of a whoosh than a flutter. Flutter is normally caused by the air traveling back through the turbo, which it would if the DV didn't open.

Have you checked for codes? An electrical issue should show up.

 

[-SnowMan-]

It's possible its not opening. If its working properly it usually makes more of a whoosh than a flutter. Flutter is normally caused by the air traveling back through the turbo, which it would if the DV didn't open.

Have you checked for codes? An electrical issue should show up.

Haven't pulled codes.The new DV will be here tomorrow so its going in soon. I was just curious really.

 

[xatnys360]

I've experienced this before - check the electric connector that plugs into the DV. If the connector isn't solidly locked onto the valve (or if the wiring is damaged), you'll get a bird-chirp-esque flutter.

I've had the tone of the flutter change over time (across a couple of days, before I realized the source of the problem) as well. My best guess is that the connector was mostly engaged, but vibrations would shake off contact just enough to cause an intermittent signal - causing the valve to work, but intermittently. Over time, the connector worked itself off more, causing longer intervals of intermittent disconnect, causing more pronounced flutter.

 

[-SnowMan-]

The original reason I changed the valve was because I suspect the electronics in it stopped working. The Rev D. I installed worked fine, but it was just really sticky. So you may be right.