My 97 Astro is having a hard time starting

I have a 97 Astro Van that has a hard time turning over when starting. I hold the key in the starting position and pump gas and to about the count of 20 if finally catches. I can immediately kill the engine and restart it just fine. But after sitting for a bit the same problem comes back. Any suggestions would be most welcome. Thank you.

Sounds like wires and/or cap and rotor, how many miles since last tune up? GM wires on newer Astro's are only good for 36K due to smaller diameter and extremely high voltage.

I'm not sure about a 97...
but a lot of older v6 astro's have fuel pump relays bad and the engine will not start until the oil pressor sendor detects enogh pressure.
You may want to check the fuel pump, relays, and fuses...
Good luck.