wooshing

Have just started getting a strange wooshing noise when accelerating which goes away when you lift off and run at a steady speed. Touch the throttle and you can hear it rise and fall when you lift off. It is getting quite loud now and I can't work out where it is coming from, anyone got any ideas?

Hi ppl, I've a C220CDi (W203) and recently I notice a strange wooshing sound from the engine as I rev it ( as opposed to the normally whistling sound when the turbo kicks in). I think it sounds like air being squeezed out, possibly out of a split turbo hose or pipe. Has anyone come across...