Originally Posted by willwren
Bill, how about running at idle from a cold start for a few minutes of troubleshooting WITHOUT the SC/WP belt?
I already tried that, but only ran it without the belt for a minute or two, and I couldn't really listen for noises at that time because I was alone, and the idle was higher than normal due to the ECM being open loop before the engine reached operating temp. The idle noise is more pronounced at the lower idle with higher vacuum achieved after warmup.
I also wonder, though, what could cause noise during acceleration too, as I already noted (in this post or another one, I don't remember where I noted it). In summary, there'* a noise at idle and there'* a noise during acceleration, and at this point I don't know whether or not the 2 noises are related. I originally decided to replace the supercharger due to the acceleration noise because there was noise at idle too.