Van ran great. Next time I started , barely ran. Never stalled, but no power when stepping on the gas. Hard to start, runs rough, Seems like it running out of gas. Gauge has been erratic. Pump, filter, sending unit?
Feul pump? on 1993 GMC Vandura 2500
I was experiencing the exact same problem with my Vandura. It was my fuel pump. It was barely producing enough pressure to operate the engine.
You can verify this by checking the fuel pressure, otherwise you'll be guessing if you replace these items, and they may not be needed.