So I have had the Evo 10 bov on my RA for a little over a month...

Today was a cold day and the car started making a weird noise - at a slow speed i would rev the engine and the bov would 'woosh' followed by two or three '*****' noises

does anyone know what it might be or experienced this as well???

thanks in advance for helping!

 

sound like chattering? or fluttering? kinda like a vibrating fart?

 

Yes, is it a bad thing? should i be worried?

 

dont be worried its normal

 

I thought that fluttering sound is compression surge, isn't that not so good?

 

Compressor surge is not good for a turbo. As the turbo is slowed down to let car back out its inlet.
Check you vacuum line going to the bov

 

Yes, I kind have the same problem. mine it's the vacuum line..

 

it most of the time compresser surge but we got plumbed back valve that make that noise in the air fillter flutter air going back through your intake pipes

 

That was hard to read.... Learn to speak English please.

 

dont be a smartarse