High Pitch Whine 2007 Tahoe

[Plimbob]

I have a high pitch whine in my 07 which I can hear only at idle. When it's first started it is less pronounced in park but detectable in drive and reverse. After it's warmed up it mostly constant
regardless. It is not loud enough to hear while driving with window opened or closed. I have checked the alternator and brake pump and it doesn't appear to be coming from those.

I thought it was possibly a vacuum leak but with the hood open I can't locate it, doesn't mean it isn't but I can't locate it if it is.

Feedback is much appreciated.

Thanks,
Tim

 

[Big Mama]

Any changes in drivability or other things not working? Any change if AC or heater is off or on? If you walk around your rig with it running can you pin the area down like left front etc?

 

[Marky Dissod]

I have a similar whistle at idle.
I have changed three throttle bodies and 3 idle air control motors, each, for a total of 9 combinations.
Yes, mine is a GMT800, but I'm still interested in how this turns out.

 

[Doubeleive]

I have a high pitch whine in my 07 which I can hear only at idle. When it's first started it is less pronounced in park but detectable in drive and reverse. After it's warmed up it mostly constant
regardless. It is not loud enough to hear while driving with window opened or closed. I have checked the alternator and brake pump and it doesn't appear to be coming from those.

I thought it was possibly a vacuum leak but with the hood open I can't locate it, doesn't mean it isn't but I can't locate it if it is.

Feedback is much appreciated.

Thanks,
Tim

take the belts off, start it up for a minute and see if the sound is gone or not