Step by step guide on how an automotive knock sensor works.
Step 1 - A knock sensor, which is located somewhere
on the engine block is designed to detect engine combustion knock. This sensor performs
this duty by utilizing a temperature sensitive diaphragm which is surrounded by
piezo ceramic. Once the sensor has been activated it sends feedback data to the
PCM (computer) which in turn uses this information to make adjustment to ignition
timing and fuel consumption properties. This sensor helps the engine run at maximum
performance and economy while safeguarding it from detonation or pre-ignition (ping)
which develops when combustion temperatures reach maximum levels.