Recall: I took the Avalon in for the recall. They kept it all day and got it all fixed (I guess). Belt Tension: They tightened the A/C belt slightly and the noise is gone.
Other: The dealer (Precision, Tucson) called me late in the afternoon. The service rep told me that the Avalon's water pump was weeping fluid, that I needed to have it changed. He also told me that they recommend replacing the timing belt and the power steering belt as both are six years old. Estimated charge: About $800.
I declined on this extra work as I have never noted any fluid loss in this car and, of course, you can't see the water pump without removing the timing belt cover. Anyhow, all is well as far as I can tell! Thanks to all for your advice. jor