Hey guys! First post here. Any help would be greatly appreciated. I have a 2008 G37S Coupe with about 68k miles.

A few weeks ago I got my serpentine belt changed, along with my oil and oil filter at a shop that I trust. A few days after that, I noticed that the exhaust sounds different. There is a whistling sound that seems to be coming out of the exhaust as well now.

In all honesty, if I hadn't been driving this car for the past number of years I would've thought that it actually sounded better. It's almost like an aftermarket exhaust. But of course, something is different. I don't hear it when I'm idle, but when I press down on the accelerator the whistling sound accompanies the normal exhaust note. Aside from this new noise, the car runs just fine.

Has anyone else had this issue before? Thanks!

 

theyve added a supercharger for you...
.. check the belt for play

 

And the Flux Capacitor

Telcoman

 

All jokes aside, take it to a shop and have your car lifted & checked. I'm having something similar, but mine rattles as well which is quite common. Keep me posted on what it ends up being. Having them figure out what the issue is can't be that much of a hassle.