Two weeks ago, my 02 coupe started a high pitch noise when my wife and I were returning from a cruise to the Royal Gorge with some of the RMCSC members. The noise was not there on the trip to the Gorge. Never heard it before, nor had my wife; 20K miles on the clock. Noise continues when engine running, but coupe not moving, so its not the tires. Haven't investigated yet, but my first thought is the serpentine belt apparatus. Since I drive about 0.6 miles on a dirt road with some washboarding, it may have lost some of it's tension. If not, then I guess I am in for a lot of troubleshooting. I will be watching your thread with great interest, hoping we both get the solutions.
Barrett