It was an idler pulley. The cheapest thing connected to the serpentine belt. Incidentally, I had to drive to Houston Friday on the hottest day of the year there. And the blend door failed. You are my new diagnostician.
Comes from a natural curiosity and doing 98% of my own work. I'm getting to the point where I'm more willing to pay someone, but I know if they are blowing smoke up my rear or not.