Knock detected fault

[Mark Ashworth]

Can anybody help me with this.

According to the ECU fault codes I have a knock sensor fault.

The knock sensor is fine I've changed it, however I get a knock detected error.

I dont know  if this is a real error or not. I expect every engine to knock at some point, isn't that the whole point of the sensor to adjust ignition advance?

In case it isn't I've ran a few tests with my oscilliscope and can see what looks like knock, but not sure.

I'm also surprised the ecu is detecting knock as it does not do this below 3k rpm and only really does it if I keep blipping the throttle over 3k.

The engine is fairly quiet, I cannot hear the knock even with my stethoscope. 

I also run 97 ron fuel, so I'm surprised if this is knock especially as it does it when not  even under  load at 3k.