I have a Question about mt car....?

So, i have a 1993 cadillac seville and it runs like crap, I was wondering if maybe someone could maybe help me out and tell me what might be wrong with it. When i start the car i have to rev the engine so it dont stall, and when i finally get it to go, it spits and sputters and back fires until it gets going. i have fixed so many things on it such as, the starter, spark plugs, all spark plug wires, distributer cap, and i could name so many more but it would take all day, i dont know what else to replace. any suggestions?