1999 Chevy lumina ltz hard to start, and quits when given gas

Sounds like my experience with my 99 Lumina 3.8 LTZ,don't waste your time or money on anything until you read this. Intermittenly at first: rough idling.stalling,black soot from the tail pipe, dying out coming to a stop,it would start but would hunt to maintain rpm's to idle and die. Checked cylinder pressure,new plugs,replaced idle air control valve, fuel filter,fuel pressure regulator,throttle position sensor,fuel pump ( expensive and difficult as it is in-tank) I searched the internet everywhere for advice and never came across this :My shade-tree mechanic brother REMOVED the MAF sensor. Although it idled roughly, it did not die out,even took it for a short drive, which proved that the MAF sensor was faulty. Replaced it with a new one and I love my car again !Advice- remove the MAF sensor ,if idle improves,it most likely needs replaced.Cheap and easy fix!

replace the fuel pump relay! problem solved!