I have a 1994 LeBaron 3L V6 making a high pitched whistle noise at idle after the car is warmed up. Took it several places and they have been unable to pinpoint the cause of this noise. Please help. Embarassed to drive car

 

Could be a vacuum leak, but they usually result in a rough idle. If it's a leak, you can sometimes pinpoint it by holding one end of a tube to your ear and searching for the leak with the other end.

If it's a screech and not a whistle, it could be a loose belt or a bad bearing. A good mechanic will have a mechanic's stethoscope which is very helpful in finding a bad bearing.

 

both mechanics checked for a vacuum leak and removed the belt and the noise continued. Not sure if they checked the bearing but I know they used a stethoscope to try to find where the where the high pitched whistle was coming from