Recently my S40 T4 has developed a low droning noise which seems to emanate from under the bonnet. It only occurs when the car is moving, not whilst idling - also it appears to go away when the car is turning left! If anybody has any idea what could be causing this strange noise, I'd be awfully grat...

[quote="seanwil"]Hi Vollic75, I am experiencing a similar problem to the one you reported in this thread and was wondering if you found the root cause and could let me know. My car is a 2001 V70 2L Turbo. The rpm fluctuates up and down when idling by a few hundred rpm when the aircon is on...