high-pitched whistling or whining sound - turbo engine sound?

[cetaphil]

I've been driving the Volvo S60 2.0T LPT (light-pressure turbo) for 2.5 years now.

Recently for the past few days, I notice that whenever I start driving and depressing the accelerator pedal, a strange high-pitched whistling or whining sound appears. This is different from the usual rumbling low-pitched engine sound. This high-pitched sound gets louder when I depress the accelerator pedal more; it becomes softer and then disappears when I release the pedal. If the car is stationary and the gear is put to "P" and not "D", the high-pitched sound does not appear when I depress the accelerator pedal.

The service consultanat at the Volvo dealer said that this high-pitched sound is due to the turbo or turbine engine - wear and tear is the given reason. There is no way to remedy the sound unless the whole turbo is replaced, which costs me few thousand dollars.

Is this high-pitched sound really due to the turbo? Or is it due to something else, like gear or engine? Does that mean that cars with no turbo will not have this problem and those with turbo will definitely experience this after few years due to wear and tear? How to remedy this problem?

Can anyone help?
Deeply appreciated.
Thanks.

Regards. Cetaphil

[Slanter]

You may not actually need a new turbo. My first thought is that you may actually need to replace the muffler. Turbochargers virtually always make a whistling sound to some extent - every turbocharged car I have ever owned (3, so far) or ridden in had an audible whistling noise coming from the engine. It is possible the bearings in the turbo are wearing out, as that will make the noise worse, but it could simply be your muffler or another part of the exhaust system is starting to fall apart.

[cetaphil]

You may not actually need a new turbo. My first thought is that you may actually need to replace the muffler. Turbochargers virtually always make a whistling sound to some extent - every turbocharged car I have ever owned (3, so far) or ridden in had an audible whistling noise coming from the engine. It is possible the bearings in the turbo are wearing out, as that will make the noise worse, but it could simply be your muffler or another part of the exhaust system is starting to fall apart.

Some suggested that it is the transmission problem - worn out pinion bearings. Is this possible. Thanks.

[nigrafeles]

I have a subaru legacy that does the exact same thing you are describing. I can only hear it when I'm going over about 65 or have the engine reved up high. I can also hear it at low speeds (aka idling) when the passenger door is open, but not the passenger window. I bought the car new, and its less than a year old. I've kept up on all the maintainence and it has about 13k miles. A friend thought that it might be the air filter, air filter housing or the idle control motor (air filter needs changing soon). Any ideas?

[lilviper]

You may not actually need a new turbo. My first thought is that you may actually need to replace the muffler. Turbochargers virtually always make a whistling sound to some extent - every turbocharged car I have ever owned (3, so far) or ridden in had an audible whistling noise coming from the engine. It is possible the bearings in the turbo are wearing out, as that will make the noise worse, but it could simply be your muffler or another part of the exhaust system is starting to fall apart.

most turbo systems dont require a muffler.. the turbo acts as a muffler

check the intake piping.. as well as listen with the hoood open for either that sound or a sound like it with a little bit of grinding/whine.. bearings make a distinct sound when they are about to die. do some trouble shooting.. have the wife rev the engine while you are in it ... it could be something as simple as engine mounts where as you never noticed the noise becaue they isolated the noise from the chassis.. look online for a service manual. or go to the library and look for a book on the vehicle.. usually there is alot of information there..

[ashemoto]

It seems that the sound you describe should be related to the transmission if it does not appear or is not present when the car is in the "P' mode. It would be a good idea to check out this area before anything else.