Question C7 Noise

[Nimm]

Firstly I have a C7 GS with automatic....Was driving around town this afternoon and noticed that while acelerating and decelerating that there is almost a whistling whine when I do that. I changed the drive settings on the muffler thinking maybe it is an exhaust issue and that change nothing so maybe there is a small hole in the exhaust.

Anyone have a similar experience

 

[Srgentpepr]

Firstly I have a C7 GS with automatic....Was driving around town this afternoon and noticed that while acelerating and decelerating that there is almost a whistling whine when I do that. I changed the drive settings on the muffler thinking maybe it is an exhaust issue and that change nothing so maybe there is a small hole in the exhaust.

Anyone have a similar experience

Belt tensioner pulley needs to be replaced. It’s a common issue.

 

[Nimm]

Yes, it was the belt tension pulley, parts ordered from US,. 5 more days

 

[Canuck604]

So I decided to pull the Range AFM disabler off and listen for weird sounds and sure enough. While in V4 around 50KM/h and speeding up in V4, clacking sound that goes away when V8 engages, from the internet sounds like its the belt tensioner, will call Carter GM for parts costs and will replace myself, don't seem difficult. Video link below if anyone is thinking of changing it also. Regular C7 link only I believe

 

[Canuck604]

So, it was the Belt tensioner, took about an hour to do it if you go in calm and with the correct size tools and a flashlight to see the bottom bolt

 

[19C7GS]

Damn mine might be suffering from this as well now that I saw this video;



Any news OP? Was it actually the pulley? I thought this was a normal sound from any V8, the microphone picks it up weird in that video but in real life it almost sounds like a supercharger whine if you have your windows down. It doesn't sound abnormal to my ears but I don't have another Corvette to base it off of.

 

[19C7GS]

I checked my pulley and it looks pristine still. So does my belt. Engine still whines but it sounds like a healthy whine not a pulley going bad and squealing or squeaking.

 

[Canuck604]

Hi 19C7. Can you put your ear on the noise. Some older mechanics get a metal rod and put the metal rod on different parts to diagnose. Just make sure you dont lose your ear or face.

Could be any of the following, but I would if I had to guess say that it is the belt tensioner. But could be any of the parts attached to the belt that is failing
Lets see if the OP can shed more light also

Chevy Corvette: Whining Noise → Diagnosis | Drivetrain Resource

If your Chevy Corvette is experiencing a whining noise, its is often going to be caused by something in the engine compartment. The likely cause of whining noise will be determined by when you hear the noise, and under what conditions With that in mind, this page is divided by when you hear the...

www.700r4transmissionhq.com

Chevy Corvette: Whining Noise → Diagnosis​

October 3, 2019 by Jason
If your Chevy Corvette is experiencing a whining noise, its is often going to be caused by something in the engine compartment. The likely cause of whining noise will be determined by when you hear the noise, and under what conditions
With that in mind, this page is divided by when you hear the whining noise, and common causes under those conditions.
Before you go any further, is the whining noise constant when you rev the engine? Or does it not change with engine speed? If it changes with the engine, it’s most likely going to be an accessory bolted to the engine (or the radio, shut it off and see if it stops). If it stay constant as you rev the engine it’s going to be something else.

Chevy Corvette Whining Noise When Accelerating​

A whining sound when accelerating is almost always caused by a bad accessory attached to your Corvette’s engine. Here are the most common causes of whining noises when accelerating:

1. Bad Alternator​

When an alternator is going bad, it’ll often begin to put out a high pitched whining sound. It should also be accompanied by the battery light. If not, it may not be the alternator making your Corvette whine, although it doesn’t rule it out entirely.
A typical alternator

2. Power Steering​

The power steering pump is a very common reason why your Chevy Corvette might whine when accelerating. If it gets too low on fluid they’ll make the it’ll whine a lot. You need to check the fluid level and fill it back up to the factory fill line.
The pump can also go out. To determine if it is the power steering pump, turn the wheel left and right with the vehicle sitting. Does the sound get louder while turning? That’s a great indication that it is probably the power steering pump making noise. All of your engine accessories will change their wine depending upon the RPM. Only the power steering pump will change with RPM or the steering wheel.

3. Water Pump​

When the water pump goes bad, it’ll make a squeaking sound. It’ll often sound like a deeper whine than a bad alternator.

4. Worn Serpentine Belt​

Your Corvette’s serpentine belt is responsible for taking the motion from the crankshaft, and using it to turn all of your accessories. When it goes bad, it’ll cause a high pitched whine. This is particularly true when you first start the vehicle. There’s more on this in the whines while starting section directly below.

Chevy Corvette: Whines When Starting​

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Whining when starting can be frustrating to diagnose, since you constantly have to start and restart the vehicle to duplicate the conditions that caused the sound to begin with.
Here are the most likely causes of a vehicle whining when starting:

​

1. Serpentine Belt​

Your Corvette’s serpentine belt turns all of the engine accessories. As they go bad, they begin to glaze and stretch. When a serpentine belt stretches, it doesn’t grip the accessories that it is turning as well. It’ll squeal until it grabs all the way. They are really affordable.

2. Radio​

The radio can accept interference and cause noise when starting the vehicle. This is a great place to start, since it only takes a second. If this does stop the noise, there’s more on this directly below.

3. Starter​

The starter may not be fully engaged with the flywheel/flexplate. Or, it could be a situation where it is having a hard time disengaging. If it is even a little bit out of alignment, it’ll be enough to cause a whining noise.

4. Transmission​

A bad torque converter can cause a whining sound when starting your vehicle. A good place to start would be to check the transmission fluid. You’re going to want to check it for both color, and metal content.
If you see any flecks of metal on there, it is probably going to need serviced. As long as you have the dipstick out, go ahead and check the transmission fluid color. It can tell you a lot about the health of your transmission.

Stereo Making Whining Noise​

If your Corvette’s stereo is making a whining noise, it is usually caused by a condition known as “alternator whine”. Alternator whine is a product of a drop in voltage between the radio and the alternator itself. It is usually way more noticeable on the A.M band of the radio. You’ll hear it match the acceleration of the vehicle.
Alternator whine is almost always caused by a corrupted ground wire to the radio. Once a good ground is restored it should go away. Here is a great page with way more info on the subject.

Conclusion​

Good luck figuring out what is making your Chevy Corvette make a whining noise. If there is anything that you would like to add, please leave a comment below.

 

[Canuck604]

19TC check this video if you are a do it yourself kinda guy