So my 2000 Astro AWD started making this noise upon cold start. After a few minutes it will get a bit better. Everything seems to be in order but obviously something is off. Most recent work done was to replace the alternator and the battery. I can't seem to find a connection between the repair and the noise.
Note that I have been getting P0420 DTCs and had not yet gotten a chance to investigate since this appeared.
I've done a little reading and I'm not sure if this could be the worn distributor, or, something much worse. I believe that the disty is original and I'm approaching 300k miles. I'm hoping you'll recognize this noise which will help me find it and fix it. Budget is very tight and we're already down one vehicle.