High Pitch Whine from LS6

[LAC]

I am an owner of an '01 Z06. I am getting a high pitched whine from the front of the motor at idle. Sounds like a bearing. The local dealer has replaced the belts, changed the intake, and air conditioning idler. The noise is still there. The tech has removed all the belts and the noise was still audible. I was told by the service writer that he has other Corvettes with the same problem... so far the service team does not have a clue. Most noticeable when engine is hot and ambient air tempature is in the 90's. Some have described this noise as an air or vacumn leak, but no one can fix the problem.

Anyone have a suggestion????

 

[rwd]

I can't tell you what it is, but I can't give you a few ideas on how to find it.

Get a small wooden dowel (maybe 3/8" or so, something rigid) around 24" long and a similar length of rubber garden hose or the like. Put one end against your ear. Use the hose to screen out extraneous sounds and locate the source area, and/or place the other end of the dowel against the accessory drives, compressor, etc. to listen to them for the same purpose.

If there's a bad bearing, for example, you should be able to isolate it that way. You didn't mention if the noise changes pitch when the revs are increased, btw. That'll make a difference, as well.

 

[FLYNLO]

If it is an air or vacuum leak, it will show up in the codes. The car knows how much air it is "collecting" and how much it is actually receiving. Have you checked codes? And an air leak should throw a "check engine" light.

 

[LAC]

Dealer replaced idler pulley on acc. belt.. we will see if it takes care of the problem

 

[FLYNLO]

I listened to my car and noticed what appears to be a little whine. It is not bothersome and it is probably endemic to a car that needs a lot of air. What y'all may not realize is that a car that makes a lot of power needs a lot of air to make that power. When you rev it, you can hear the air going in and it has a tendency to "whistle" just a bit whether it is airbox restictions or something the air is hitting going thru the MAF or throttle body. Anyway, the noise I am hearing and the one you are hearing may be different because what I hear is normal.

 

[LAC]

The sound mine was or is making can be heard across the street, it is very pronounced.

 

[TAC]

The sound mine was or is making can be heard across the street, it is very pronounced.

Could it be described as a whistle sound? My '03 makes a loud whistlle noise.

 

[LAC]

TAc,

No is is not a whisle.. very high pitch sound... really sounds to me like a dry bearing.

 

[vettepilot]

Do you think you could be hearing the alternator? Try changing the electrical load by turning on or turning off large load electrical devices, headlights, A/C, rear window defogger. See if the sound changes in any way. Is the sound more pronounced immediately after start-up, then slowly dissapates?

vettepilot

 

[LAC]

Dealer replaced a pulley on the front of the engine.. air conditioning. Seems to have fixed the problem.. I always said it was a bad bearing whine.