[AUtyger]

My '91 240SX 5-speed suddenly began to miss fire and hesitate. After new cap, rotor, plugs, and wires, I found that #4 piston seemed to have no life. You could disconnect the wire or the injector, and notice no change in the extremely bad idle. I swapped the #4 injector with the #1 injector, and the problem now is on the #1 piston. So, I ordered a new injector, installed it, and still have a really bad idle. Must I remove the fuel rail, clean it out, and reinstall everything? Am I barking up the wrong tree? I bought the car, as a toy, a few months ago, and I am a Nissan newbie. Any help is greatly appreciated!