Just had the engine management light on. And aftee scanning its saying theres an error with my knock sensor on my octavia vrs tfsi 06 plate. Any ides what could be the problem and what is a knock sensor and what it does??

A knock sensor alters ignition timing. There are two bolted to the front of the block, as the engine knocks when the timing needs to be altered the resistance of the sensor changes. This is fed back to the ecu which makes the adjustments, it's a closed loop so it's always doing it.

It is critical when fitting one it is torqued up correctly for it to work, over tightening it will break it.

Thanks. So if its the sensor what could be the potential problems apart from a dodgy sensor.

Sensor, wiring, control unit.

Thanks. So if its the sensor what could be the potential problems apart from a dodgy sensor.

Sorry for the last post. Thanks for the advice.