Hi, looking for some advice on a problem i have with my 04 Mazda 6 2.0L Petrol 60K on the clock. Over the last few weeks i have noticed a noise coming from the alternator belt area, particuarly when the engine is cold. The best way i can explain it is a rattling sound, similar to a loose exhaust heat shield I have checked for anything loose and all is ok.

The noise does get a bit quieter as the engine warms up and looking on other sites it could possibly be the belt tensioner at fault but this is only a pulley with a bearing which i cant see how this would make this sort of noise.

Amy comments much appreciated