What does a GM knock sensor do?
The knock sensor picks up vibration and sound coming from the engine block, turns it into an electronic signal and sends that signal to the engine control unit (ECU). The car's computer then judges the information and determines whether or not ignition timing should be altered. via
What is a knock sensor 2 circuit Bank 2?
The knock sensor monitors engine “knock”—this indicates that the engine is experiencing unusual combustion in the form of detonation or pre-ignition. Code P0330 may be set when your PCM detects a problem with the #2 knock sensor or its circuit. The knock sensor is usually bolted or threaded into the engine block. via