Grinding, squealing noise in engine

Bokersmith
Mar 12, 2007.

Engine starts fine, car idles high until warm, at higher rpms squealing is blocked a bit but still there, when idle drops after warmed up, car runs rough and makes a grinding, almost squealing noise; sounds like a grinding wheel, cyclical - almost like something is spinning, catching, then spinning again. Similar sound occurred on another car when the alternator was going bad?
Vitals: acura, integra, 1990, 149K, 1.8L

I just spent some time listening to it at idle and the noise is coming from the opposite side. It seems to be coming from the distributor - and over time really gets high pitched and noisy.