strange sound after acceleration

[Jints1]

When I let off the gas after accelerating I get a whirring thump like a card in a bike spoke but deeper. I thought the fan might be hitting something but it is only after I put it down and let off right away. Anyone know what that might be?

 

[Chris Cornett]

I think you are talkin about turbo sneeze?? Do you have the stock airbox. If no then that is probrably what you hear. It is boost built up sneezing out from the turbo.

 

[Jints1]

turbo sneeze

I have a k&n cone on it. So how do you get rid of this turbo sneeze? It is an ugly sound and I'm sure it can't help my power.

 

[dconnor]

It's pretty much just part of owning a turbo....

When you come off the gas suddenly while "in the boost" that built up pressure has nowhere go when the throttle blade closes so it basically escapes the only way it can, back through the turbo & out the air cleaner. You can alleviate it a bit by rolling off the gas a little softer OR by installing a blow off valve which IS effective, but gives that "cool" chuff/zing sound that ricers are so fond of... might have them following you around like puppy dogs.

Doug C.

 

[MiamiGN3.8]

one way is to get a blow off valve. I get the same noise and i hate that noise too. Now i hate those rice bov's but one , the greddy type r. I used it and it's very quit .

 

[onefastjackass]

You are gonna have the half dead bird flapping around sound(at least thats what mine sounds like).

Up to you but FYI no one has ever proven that a blowoff valve on these cars does anything except change the noise.It will not help or hurt power.Remember you are off the throttle when it happens.Ricers run them to keep the turbo spooled between gear changes.With an automatic the turbo stays spooled so no advantage at that point.And no one has proven that it adds to turbo life on these cars.
So I would just accept it as a normal noise and keep my money in my pocket or use it for things that actually help.