Volvo C70 2.0d strange engine whine noise

[BertoneP]

Hi,
I have a 2008 Volvo C70 2.0d 136 BHP that now suddenly makes a whining engine noise when accelerating.

The car runs fine otherwise and has lots of power and revs without any hesitation.
The car has 117.000 kms on the odometer and I have not changed the timing belt , waterpump nor tensioners etc. yet.

Have removed the oil cap to rule out PCV suction noise...so no issue there I think. Also tried to check the upper intake plastic piping parts but they seem look fine without any cracks...

Could it be the bearing from the alternator or a tensioner bearing ?

Here is a video on the noise: https://www.youtube.com/embed/gby3FEZbtlI
Any clues ????

Thanks for you help !

[lordbasil]

fan belt slipping/squealing??

[BertoneP]

It's more of a whining noise rather than squeaking noise...

I'm inclined to think it's an alternator bad bearing noise.

[dingov70]

Remove auxillary belt & run engine for a short while , if the whirring still occurs change cam belt & idler / tensioners ASAP and possibly water pump as well .

If the noise has stopped , spin one thing driven by the aux belt at a time feeling for roughness & listening for any noise or movement other than rotation from a bearing

[BertoneP]

Thanks for the tip. But if I run the engine without the aux belt on, will that trigger any fault code on the dash ? And is it safe to do so?

[dingov70]

You can run without an aux belt as it only turns alternator , air con pump & possibly power steering pump , so it will not trigger a malfunction light and YES it is perfectly safe . I do it quite often for just the reason you have enquired , it is a quick & easy method of eliminating potential problem area's