by hilljb » Thu Mar 23, 2017 2:00 am
I'd remove the serpentine belt and start it up... not for long, but long enough to see if the noise goes away.
Otherwise, assuming this is present at idle, you can use a longish length of tubing, placing one end at your ear and using the other to poke around in the engine bay to try to pinpoint exactly where the noise is coming from.