High-pitched wheezing sound from engine?

[mahu]

Just took the NV for a drive around the block to celebrate the fan install and my wife and I both noticed a high-pitched wheezing sound coming from the engine when accelerating. Could only test it at 10-20mph in our residential neighborhood and also can't hear it at higher speeds due to road noise surpassing it. It occurs as soon as I touch the accelerator however gently and is the same in drive as it is in park. It gets louder the harder I step on the accelerator and it goes away as soon as I let up. And it's very distinct and have never heard it before. Had regular oil changes at 3500 and 7000 and are at 7800 miles now.

Thoughts? Thanks!

Edited June 30, 2016 by mahu

[ASD Dad]

Is it only under load so you have to be driving or can you sit in the driveway with the hood up and just goose the throttle to look for the sound?  

 

First guess is a loose hose/fitting causing a vacuum leak.  Check all hoses and clamps along the intake, air box lid, etc.

[KMG]

I too was working on my van and heard a wheezing noise but quickly realized it was my labored breathing.  Man getting old sucks!

[Glidedon]

wind noise from fantastic fan?