Hi, I have a 2000 Honda Civic 2 EX. It randomly shuts off while driving at speed, accelerating, or while not moving at all. It does this while warm or cold. The electrical part of the ignition has been changed and the fuel/air filters changed. The car continues to buck and jerk and completely cut off at times, and then restarts after a few seconds, carrying on like nothing happened. Sometimes it continues to jerk, or just won't start at all momentarily. Please help me before I pull all of my hair out. The dealer has done all checkups and tune-ups. . And can't find a problem. They replaced the Cat because that's what code the ECU receives. I don't know what else to do. The OBD check engine light comes on again (2 months after the cat was replaced) and it shows two codes, the one for CAT back pressure efficiency and one for ???? it doesn't know. Please help me. It's got 40,000 miles. It has been doing this for four months and progressively getting worse. I could barely make a 6 mile trip today.