1995 jimmy 4 months engine sputtered,engine light on 6 mos; car cranks wont turn over complete tune up, fuel pump works gas through filter, antilock light came on not long ago just before complete breakdown;

start by checking timing.

Check engine for a spark at the sprak plug wires.
If spark is present, spray carb cleaner into the intake ant try starting the engine if it starts then fuel isn't reaching the cylinders (bad injectors or injector "spider" part where all injectors meet).

The engine in your “Jimmy” is a “Vortec”. A Vortec engine has a “Higher Fuel Pressure” requirement than a “Non Vortec” engine.

If you’re reading 45 psi at idle (or with KOEO) then that’s your problem. We’ll get into the causes later. Don’t want to hit you with everything all at once. For now using a “Fuel Pressure Gauge”, confirm the “Stats” below and get back to us.

Fuel system pressure with ignition key on and engine off (55 – 61) PSI

Fuel system pressure at idle (55 – 58) PSI

Fuel pump pressure with return line briefly restricted. (61) PSI