On my SDi (with air con) I have noticed, after looking at the belt as it has been making a slight noise for the last year, that the tensioning pulley shakes around all over the place while the car is idling. Is this normal?

May thanks

Stu

No, it should run smooth. Possible causes, belt worn and slipping (you can give the belt a light spray of water and see if it then grips properly for a few seconds). Other causes, partly seized aircon pump or alternator clutch.

Ah ok then, it wouldnt just be that the tensioning spring is on its way out?

From my previous post it could well be the air con pump partly seizing, but the noise the belt makes goes away after 1-2 mins of driving, which is what makes me think its the pulley....... might not be though.

Thanks for your help though, guess i'll look at getting the air con serviced

The noise could be the belt is a bit slack and usually squeals when cold. If you have a high mileage or few years old car you should be changing the belt and tensioner, they don't last for ever. Not as serious as worn cambelt & tensioner but still worth changing.