GM-GMC: 1991 Chevy Astro Van -- No Idle, chevy astro van, chevy astro

Question
I have a 1991 Chevy Astro Van that won't idle, stay started, or drive.  If I rev the engine and force it into drive it bogs down and I have to constantly feather the gas pedal in order to make any progress at all and still can't go more than 3-4 miles per hour.  I just bought it and the seller claims it ran until he let it sit for 3 months.  Things I've done:  New spark plugs, spark plug wires, cap, rotor, fuel filter, put in 92 octane fuel with an octane booster.  I've had the ignition module (located on distributor) tested at Autozone and it checks out good.  I'm a shadetree mechanic and have no way to test fuel delivery pressure but have tested the fuel pump and it does run for about 3-4 seconds and then stops (with ignition switch in "on" position.  I'm scratching my head on this one.  Any help, suggestions, test procedures would be a great help.

Answer
It sounds to me like you are well down the road to diagnosing this problem.  Sounds like you have replaced everything up top except for the ignition coil.  You will need to get your hands on a fuel pressure tester some how.  Some parts stores have a loaner program.  Test it at the fuel filter, it is the easiest place on those vehicles, install the tester and have someone crank the engine over while you watch the gauge. See what you get for pressure.  Sounds to me like it is the only thing left?!  I would be knocking on the former owners door too.
Hope this helps