Below is another post on the topic from the Saturn fans website....
Key1
Re: Ultra High-Pitched Sound / Outlook
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Quote:
Originally Posted by lzwhb2
It's actually the transmission making the noise and NO, there is nothing wrong with it. This is recognized as an issue, but merely from the standpoint that the noise is annoying. A fix is being worked on to resolve this. It has to do with the fact that after you shut the vehicle off, there is still power to the transmission among many other modules in the vehicle. What you are hearing are the solenoids inside the transmission that are driven at a high frequency. When the modules "power down", usually a few seconds, the noise goes away.
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