I decided to just get the oil change and kick the can down the road and deal with the noise some other time. Seems like pretty smart thinking, right?
After I had the oil changed I was talking to the manager, Marvin, who I have dealt with for many years with all our family's cars. I told him about the noise, and said I might be bringing it back some times soon to address it. He said, I should just leave it now and they could take care of it. He said it would probably be an hour, and about $200. He said it could be something serious that would take more time and money, but he seems pretty confident in what he thought it was.
45 minutes later and $162 later, my car was fixed. The noise was gone. Now that's service. No extra fee, no BS, just knocked it out.
Yea, $162 is not a trivial amount, but it could have been any number of expensive parts. I do realize (now) that I can buy an idler pulley from Amazon for $20. Could I have replaced this part myself? Maybe I could. I have done work on my car for years with varying degrees of success. But, I had no idea what was making the noise. I have replaced the serpentine belt, the tensioner, and have removed the alternator before, but do I just start replacing parts? That $115 labor fee probably included them checking all the parts connected to the belt. Also, I did research online and descriptions of similar noises had a big list of possible sources.... transmission, breaks, water pump, alternator, etc. So, I was not confident in just taking a chance by buying a part and replacing it, and hoping for the best.
So, I feel good about the money I spent. On top of the issues of me trying to fix it myself I mentioned, the time for me to work on it would be huge. I would have spent hours finding the parts locally and hopefully having the right tools.
Now, I have time to enjoy the rest of my day not working on my car.