Where is the coil located a 1995 Chevy astro van?

The ignition coil in a 1995 Chevy Astro van is typically located on the distributor cap. Since the Astro used a distributor system in that year, the coil is an integral part of it, not a separate component like in later vehicles with coil-on-plug ignition. It sits atop the distributor, usually under a cover or shield. You'll find the distributor on the engine, near the firewall.