My sons Peugeot 206 has a 1.1L engine but whilst it drives perfectly, there is a noticable whirring noise which increases and decreases with speed. It is also evident when stationary idling and reving the engine.
I have checked the belts on the alternator and the wheels they run on and everything feels and looks okay.
Any other ideas, anyone???
The only other thing I can think of is the Alternator itself, as the noise is more prevelent in that area.

Alistair M, June 2009

check the tension bearing first before you go anywhere

big al, July 2012

Can you tell me if you found out what the problem was? I have the same thing and am trying to cut down the options for replacement.

brisprob, April 2010

Needs a new crankshaft pully, the rubber bushes have gone inside leaving the metalwork to vibrate when the tension of the pully belt is applied. I temporarily welded the gaps to stop the vibration and have ordered a new part bout £50.

Chris, October 2009

Mine has developed the same problem but has an a/c unit. From what i could feel in the engine bay it is either the crankshaft pulley or the a/c pulley that had some play. i will be testing tomorrow with a non a/c pully belt to bypass sections. when running the engine without the pulley belt on there is no whirring noise at all.

Chris, October 2009

sometimes bearings just go inside alternator even if its not been muddy and wet. let us know how it goes.

me, June 2009

The car is quite clean underneath although it does be on site as he is a plumber. As it could have become muddy at times on site, I will try out the options you have given.
The car doesn't have air conditioning, so thats one less problem.
Thanks for the advice.

Alistair M, June 2009

has belt and pulleys or alternator been in water or mud?this makes them noisy. if noise is quite noticeable then remove belt, and manually spin alternator pulley. if it is noisy should be able to hear it, or it might feel grotty. check roller and tensioner this way too. if it has aircon check that the same way. alternator is likely suspect as its quite a common fault.

me, June 2009