Gman

Has anybody had this problem yet? A few days ago we noticed a high whining noise at idle speed on Tahoe #2. It would come and go but always went away just above idle. We figured here we go again with another non-normal engine noise. This time the noise was coming from the front of the motor. I first thought it was a belt noise or a dry bearing in an idler pulley but I couldn’t find the exact location of the noise. We took it in to the Dealership on Friday and they kept it over night. Saturday morning they called us to come and pick it up. The Service Manager said they found the problem. They replaced the throttle body with a new one and the noise continued. What they found out was the butterfly wouldn’t close completely making the whining or whistling noise. They were able to manually close it and the noise would stop. So now it’s a waiting game for them to research with GM and see if they can come up with a fix. It’s probably another damn computer problem but who knows.

Other then that little set back this Hoe is the best vehicle we have ever owned. It’s a real head turner especially when using the power tail gate at the grocery store. My favorite option is the sunroof. It’s as close as I will ever get to a Vette convertible.
We will keep y’all posted on the outcome.

fredster

I have an 07 with 11K miles and it has done this a few times when the outside temperatures are down around 10 degrees. Sounds more like an unhappy bearing to me, high pitched whistle, but it could be air leaking around the TB. Whatever it is, it sure is irritating when it happens.

So far mine has only done it 1x or 2x after startup and goes away. If it continues as the temps warm up this spring I'll take it in to the dealer.

Thanks for posting your experienceI figured it would take memonths to figure it out.

Auburn

Mine had a belt noise that when I took to the dealer they initially said I needed a new alternator. After waiting for the alternator to come in, they put it on and still had the noise. Turns out the power steering pulley was 1/8 of an inch out of alignment causing belt squeal at certain tempatures/humidity levels. All fixed now. Apparently a similar problem was at the dealership on a corvette which is how they figured it out so quick.

ptboy

I am glad to read that I am not the only one. Dealer could not find the problem so said no problem. My noise happens at 1500 rpms. Drives me nuts![]

Zed 71

Finally...

ZX1100F1

Been hearing of dealers that suspect whine is caused by throttle blades manually moving blades closed and noise disappears, then they naturally suspect the noise is being generated by the throttle body when in fact it is from another source but goes away when the throttle is moved due to the slight change in RPM. There are a couple of whining noises being looked into by engineering at the moment; one occurs anywhere from idle to 2,000rpm’s (engine warm), the whine is moderately loud and a very high frequency, this is suspected to be from power steering fluid passing through the check valve in the steering gear rack. Changing out the OEM power steering fluid for Valvoline SynPower Power Steering Fluid seams to be the best solution for this problem.

The other occurs at idle in and is a suspected drive sprocket support bearing which can simply be replaced with a new part.


There is also the possibility that you have a unique problem.

AT Tahoe

Ive been having the same problem. Im pretty sure we are talking about the same noise. I created a thread about this noise as well. I have noticed that when i turn on the engine with starter button for some reason the noise is more likely to occure, but Im notsure if it really has to do with it. When I took it to the dealership, they said the noise was normal but i doubt it. If anyone has found out a sloution please let me know