2001 X5 4.4i sport 100k mi
I've noticed that my engine whines in the 1,000-2,000 rpm range but has it's usual roar above that range and the usual idle below.

The whine sounds like a child's battery operated toy (like those little battery powered trucks for kids) and is pretty annoying not to mention high-pitched. I've been reading other engine whine threads but have found that they relate mostly to installing the ipod or a new sound system which I've done neither.

I thought it was related to the cold weather but even when the car and weather warmed up more recently i still hear that duracell operated sound... it's driving me crazy

Any ideas?