Whistling Cayman

[klootzak]

For the last couple of weeks I've noticed a whistling noise after switching off the engine of by 2.9 Cayman.

It's most noticeable outside the car (much quieter inside), comes from the rear and sounds like air escaping from something, dropping away to nothing over a couple of seconds.

Seems to be louder after a more spirited drive, or could be when the A/C has been working hard.

Any ideas what it might be, or has anyone had anything similar?

k

[SV_WDC]

Have you tried seeing if the car makes the same noise when the AC is turned off?

There's a few things it can be. AC Compressor, bearing, fuel pump lead. A lot will depend on when it exhibits these too i.e. is it under load, on start up or anything else?

Think if it's on start up then there might be a bigger issue. Check YouTube, some people with Cayenne V8's filming a whistle