1995 Acura Integra need help

I have a 95 integra rs and have been having problems since the day I bought it. While I was on the highway the engine completely cut off on me n wouldn't start back up for about 20 min. It kept doing that so I replaced the spark plugs and the wires, changed the fuel filter, changed the coil, cap, and rotor in the distributer. After I did that the car ran fine but then after driving it for about 15 min the car lost all horsepower n the engine started knocking while I was driving and would not change gears going up hills. Can you please tell me all the things that can be possibly wrong with my car?