C5 Whistle Query

[eddd6]

I have a 2008 C5 2.7 V6 diesel, 68,000 miles.

 

It has suddenly started to make a high-pitched whistling noise at any speed over 30 mph, coming from either the driver's door panel or the top right of the windscreen, depending of whether you ask the driver or passenger!  However, given a faint smell of burning noticeable only from outside, it may well be emitting from within the engine compartment.

 

There's no advisory notice, nor any visible signs of a problem inside the engine bay.

 

It can't simply be a seal failure after only 6.5 years can it - and no sign of wear either.

 

Any ideas?

[Johndouglas]

Could be a leak on the turbo pipework. Check for splits.

[Porsche430]

Generally, whining noises are usually caused by rushing air. If it isn't part of the door seals, give the entire induction system a going over.

[paul.h]

It may help if you can decide if the noise is road speed or engine speed related. Can you hear the noise when the car is not moving with the bonnet up if you rev the engine - if yes then as noted above, check all the the engine air inlet piping and other under bonnet hoses - if not then it will be harder to trace but obviously make sure the door seals are in good condition, the windows are fully closed or just open a touch to see if the noise changes, alter the cabin inlet air flow rate and vents direction. Another possibilty is a fuel injector seal leaking allowing exhaust gases to escape.

[coastline taxis]

ooo i bet that engine sounds lovley when you rev it up always loved the sound of the v engines they just roar. anyway take porsche,s advice about the air leaks if your having a hard time finding it then most garages should be able to do a smoke test to see if theres a leak and its shouldnt be that expensive

[eddd6]

Thanks guys - flicking into neutral at speed doesn't remove the noise, so it must be a wind issue - but such a high pitch seems most odd - like a strangled bird.

I'll report back when / if solved!

[paul.h]

I vaguely remember somebody having wind noise from the door mirrors on the 2008 on C5.

 

Found here http://www.citroen-owners-club.co.uk/citroen/topic/21760-c5-x7-2012-right-driving-side-whistling-of-air-flow/?hl=mirror

[eddd6]

Hey, guess what - a senior moment!

 

On Friday, I had tried and failed to open the side window, which was frozen shut, but evidently I had opened it a mm or so.  No noise early on, but when the return journey came, at about +5C in the afternoon, the whistling started. 

 

Luckily I noticed before paying for a dianostic check, but kept them happy with an MOT (one new sidelight bulb the only issue), which was due anyway in 3 weeks time.

 

Thanks for your thoughts previously.

[paul.h]

It is always nice when it does not cost anything to fix. Probably when trying to open the window it was frozen in place and the motor put some tension on it so that once the ice melted it moved a bit. If it freezes again, push the switch to close it if it does not open to remove any tension.