Sounds like the boost diverter valve is bad, it's a very unreliable part and makes those types of sounds when bad. My Porsche Turbo went through a number of them before I installed billet valves and now no more problems. The diverter valves I installed were actually made in England by Bailey. Take the car to you mechanic, if the diverter valve is the problem it's a pretty easy fix unless the valve is in a hard to reach spot. The billet valves cost about $175 each.
Originally Posted by benchsound
Help. I have a 2002 3.0d x5, the car has started to make a perculiar noise when the turbo gets full boost i am getting an intermittant, mostly at the start of the journey whooshing/squealing/chatter noise, sounds like a dump valve letting off. Definately boost related. Has any one experienced similar issues.
2011 550ix Alpine White, Black, 775, ZSP, ZDH, ZP2, 2TB, ZCW
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