I have a 2004 enthusiast coupe and ever since the day I got it I've been hearing this whistle-like / low-volume / high-pitch noise coming from the background and its not the stereo. The pitch goes up and down at the same time as the RPM. Anyone know exactly what this could be? Thanks.

 

Background of what? Can you be more descriptive on where the sounds seems to be coming from? Do you have the stock stereo?

 

I have an aftermarket headunit with an amp and factory speakers still. Put it on mute and the sound still doesnt go away even while driving. It sounds like it is coming from under the hood but I'm not 100% sure. I was just wondering if this is what you're supposed to hear with the 350. Just a reminder its a very faint whistling noise that goes up and down with the RPM. Thanks again.

 

My 04 Enthus has this too, although I didn't notice it until after I installed my CAI. Not that it wasn't there before I put in the CAI, I just didn't notice it, so who knows.

 

Its called engine noise and it is coming from your stereo install, take your car back to whoever installed your stereo and tell them you have engine noise and want them to get rid of it.

If you installed it yourself this might help you out.

http://www.installdoctor.com/TechDocs/999502.pdf

 

This is my guess. A bad ground or depending on how the RCA/Speaker/power wires were routed may cause this. try turning off the amp. If you can't manually turn the amp off, if you have an inline fuse going to your amp, try removing the fuse and see if the sound is there.

 

the speaker and power wires shouldnt be too close