BMW E39 weird engine noise

With such a vague description and no attempt to locate or isolate the noise it is not surprising you have replaced the wrong bits.

Perhaps a link to the sound or even a .wav file as an attachment?

hear the noise there

Well, why not post a reply to the fellow who put the video up asking if he found out what it was? Youtube will allow you to do this.

If it were me I'd get a length of fuel hose, put it to my ear, and go hunting around to find the source of the noise before I bought any parts.

--scott

Instead of making us go to youtube and search for your problem, why not just give us the link so we get the same file that you are watching? That's the customary way to do this...

You tube - schmu tube - post a link.

Oh by the way another poster's suggestion of searching for the noise with a bit of tube (or even a stethoscope) was something I was going to suggest.

Most likely it is an accessory, so if you take the belts off one at a time you might narrow it down.

Candidates may include

water pump oil pump alternator AC fan (if it has thermal slip) power steering pump (checked the fluid lately? - it will make a din if it runs out) internal engine noise (e.g. camshaft bearings)