describing a noise is difficult from the get go, but I'm going to try in case someone has a similar experience.

When I first got it, the fit was nice and quiet with predictable engine noise on acceleration.

Lately, however, I've been hearing a slight whoosh/shhh at some rpm/load situations. It's sort of like radio static but slightly smoother and fairly faint.
As far as I can tell, there's no loss of power, and negligible mpg difference.

It may be just the sound that the engine makes, but it not being prevalent earlier makes me nervous.

I popped the hood, and there doesn't appear to be anything loose on the air intake system, so i dunno.

Anyone else heard something like this?

 

The engine makes ticking sounds, sewing maching sounds, squeaks. Apparently all normal. Some of the hissing sound you might be hearing is from the grille and air dam taking wind. I noticed this on the first test drive. I guess all my old cars had thicker windshield glass.

 

If it is occurring at or just before 4000 RPM it might be related to the VTEC transition when all 8 intake valve are opening.

 

It's earlier in the powerband than that, and most of the way through it. I posted this in the 2nd gen section too and will be following it there, sorry for the cross post.

https://www.fitfreak.net/forums/2nd-...-2011-fit.html