Dying

Sounds like a vacuum problem or a gas but the cheap way is to change the MAP sensor an change out the ignition coil an the engine temperature sensor an the main air flow sensor

I know it's a lot but it's hard to say what it is with out being there or seeing what's happening when it dies dose it like lose power or does it seem to be the gas flow an also check the PCV value as while an some of them parts you can look up online an check to see if you can clean them instead of going out an spending money

When it dies it sputters and the car shakes, then power cuts completely off and flooring the gas pedal used to be able to keep it from dying, but now it doesn't help at all it just dies and backfires like a gunshot.

It sounds like a gas problem I would start with the fuel pressure regulator then start with the map sensor then do the ignition coil then the PCV value an the spark plugs an motor temperature sensor like I said you can look online an see if you can clean them sensors an values