Hi all I have a 6t bf 07 .
I am not sure if anyone else has had this issue but when I turn the aircon on on a hot day and fie it a bit when the car is running at normal temp is the turbo supposed to have a slight howling noise when hot I know they are supposed to make a shhh noise whilst boosting up but not sure if the howling is normal and when I change gears the nov doesn't have the normal tututu noise anymore it sneezes (stock bov) I have checked the pipes they are tight but I noticed that the top pipe on the intercooler is slightly squashed I doubt this could b the issue I have also checked the fins on the turbo they seem fine appart from a slight discolouration for redonda it's normal but to me it seems like it isn't any help will b appreciated

sure its not the 2nd thermo fan kicking in mate?

lol it'll be the thermofan you can hear, turbo noise wont change.
The tututu noise isnt a BOV noise, the shh or psshh noise is.
I'd say its running 100% fine

I know it isn't the 2nd thermo kicking in cause that starts when the temp hits half way to cool it down to about 1/4
when the turbo spools up and the revs are at around 4g it's starts then when I either release the throttle or change gears it stops then spools up again with the normal sound then it'll do it again

oil starvation to the turbo or worn turbo bearing????

im going to have a look this weekend at the oil line to the turbo and give it a clean ill keep u posted