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My 2013 CD is beloved. Like anything or anyone you love its hard to admit when something may be wrong. Alas, I know in this community, you’ll understand.

The noise:
It doesn’t directly correlate with engine rpm or ground speed.
It isn't there all the time. About 40% first few minutes and decreases thereafter until its 5% or so.
It does seem to be worse when car is cold.
It seems to appear most often when coasting, not accelerating (but maybe engine and wind noise are just masking).
Its a whirring sound. Like an electric car with fake engine noise.
I have PASM but I can raise & lower noise free. It isn’t PASM pump.
It isn’t especially prevalent when turning.
It isn't related to bumps or vibration or resonance or road surface.
It seems not to be suspension related.
I can’t stop it by braking or accelerating or turning. The whirring will continue until it decides to stop.
Breaks feel fine.
Acceleration is normal.
I don’t think its hvac.
Car idles normally and has never shut off like it may with fuel pump issue.
It seems to me like its a pump or belt of some kind?

I’ve searched a bit for answers but “Cayenne Mystery Noises” have not presented conditions like mine.

Thanks.

leftlane

Is it making the noise when you are stationary? A lot of what you described sounds like a wheel bearing but if it’s there while you are stopped it obviously isn’t that.

coffeeisgood

maybe record an audio clip and post on youtube and here?

hearing the noise might help identify the noise

AdBlue

i tried. Its hard to discern over engine/wind/road noise.

AdBlue

No noise when stationary and while not always directly correlating with speed at 0 or really < 5mph I don’t hear it.

I think it is a wheel bearing (or more than one). The tone can change as the weight moves around the car. Accelerating and breaking but it wasnt tied to revs or brakes directly.

Thanks for the clue. How much you think this costs to fix? Is this a usual wear item at 105k miles?

Needsdecaf

Yeah, it probably is a wheel bearing. The tone changing as weight moves around is a definite clue there.

I haven't had to do one on my 958, but have on other cars at lower mileage.