[danfratamico]

When I floor my 2007 E90 335 (typically in sports mode), I hear a whistling/fan sound that gets louder as I accelerate. I'm worried it may be my turbo. Any idea what else this may be?

[fazman]

How many miles on the car? I have a 2008 e90 335xi FBO with 197k miles. My original stock turbos started to make a howling/siren like sound all the time at low speeds and that was the sign that my turbos were game over.

I got new stock turbos from FCPEuro and the turbo install kit. At the same time I did everything else like the motor mounts and oil pan gasket too. New valve cover (came with gasket and bolts). New waterpump+tstat kit and a bunch of other stuff.

[danfratamico]

Originally Posted by fazman

How many miles on the car? I have a 2008 e90 335xi FBO with 197k miles. My original stock turbos started to make a howling/siren like sound all the time at low speeds and that was the sign that my turbos were game over.

I got new stock turbos from FCPEuro and the turbo install kit. At the same time I did everything else like the motor mounts and oil pan gasket too. New valve cover (came with gasket and bolts). New waterpump+tstat kit and a bunch of other stuff.

I have 122k on the car. I don't hear it at all at low speeds, even under fairly aggressive acceleration. I only hear it when I'm going more than 40 mph and really flooring it.

[6Inarowmakesitgo!]

I had an odd whistling/wooshing noise in the cabin after I did my steering shaft and the rubber seal in the firewall was not seated properly. just something to check.

[feuer]

Originally Posted by danfratamico

I have 122k on the car. I don't hear it at all at low speeds, even under fairly aggressive acceleration. I only hear it when I'm going more than 40 mph and really flooring it.

What ever it is it is not mileage related. Not sure why that guy threw the mileage in the mix. Completely irrelevant.