Does the engine knock with a bad sensor?

A bad sensor itself won't directly *cause* engine knock. Engine knock is a result of uncontrolled combustion in the cylinders – often due to improper timing or fuel-air mixture. However, a faulty sensor can provide inaccurate information to the engine control unit (ECU), leading the ECU to make adjustments that *indirectly* result in conditions that *promote* knocking.

For example:

* Faulty Mass Airflow Sensor (MAF): An inaccurate MAF reading can cause the ECU to deliver too much or too little fuel, leading to a lean or rich mixture, both of which can cause knocking.

* Faulty Manifold Absolute Pressure (MAP) Sensor: Similar to the MAF sensor, an inaccurate MAP reading can lead to incorrect fuel delivery and potential knocking.

* Faulty Crankshaft Position Sensor (CKP): This sensor provides timing information. A bad CKP sensor can lead to incorrect ignition timing, which is a major cause of knocking.

* Faulty Knock Sensor: Ironically, a faulty knock sensor might *mask* the problem. If the sensor is malfunctioning and not reporting the knock, the ECU won't adjust the timing to compensate, potentially leading to further damage. But the knock itself is still happening.

In short: a bad sensor doesn't directly *make* the engine knock, but it can create conditions where knocking is more likely to occur or prevent the system from detecting and correcting the knocking. If you're experiencing engine knock, diagnosing the problem requires more than just checking for bad sensors; it requires a thorough investigation.