My first post from 9/30 was deleted for some reason.

Honda Fit 2007 made a noise for 10 days and then disappeared.
It comes at idle, no change with revolutions. It seems it is not the serpentine belt.
What could be the reason?

 

considering you are idling, it may to be worn pulley bearings.

 

I just had this issue recently and was searching for another issue on the forums when I came across your video.

You will want to investigate the idler pulley first and foremost in your serpentine belt system. Yours doesn't sound quite as bad as mine was just yet, but I don't think its going to last too much longer...check how much tension there is in the belt too, you should be able to twist the belt no more or less than roughly 90 degrees by hand ideally.

 

take a screw driver and while car is idling, touch it to suspect parts and listen to the noise. that can be dangerous so take screw driver and combine it with plastic jug as shown in this video. credit goes to eric O from southmain.

 

You guys are correct. - It was the pulley.
The drive belt was also replaced.