Can a bad knock sensor cause a rough idle?

Yes, a bad knock sensor can cause a rough idle. The knock sensor detects vibrations caused by engine knocking and sends signals to the engine control unit (ECU) to adjust timing and fuel delivery. If the sensor malfunctions, it may lead to improper timing adjustments, resulting in an uneven idle and performance issues. However, other factors can also contribute to rough idling, so it's important to diagnose the issue thoroughly.