According to the CEL I have an intermittent fault with my Knock Link sensor. The CEL comes on after about 10 mins from cold, then goes on and off for about 10 miles and eventually goes out for the duration of the journey. I have found what I believe is the sensor underneath the intercooler, bolted to the inlet manifold, but I am not sure if I am right. Has the KL sensor got a 2 wire electrical connector and 2 vacuum pipes going to it? If so, can someone tell me how it works? ie how does it sense knock? Car is MY00. Thanks.

 

I believe the knock sensor detects the unique sound wave of pre-ignition or knock and this is then displayed on the LED panel inside your car.

Darren

 

I haven't got a Knock Link so the question is, how does the sensor detect knock in order to tell the ECU?

 

The car has its own knock sensor for the detection of DET so the ECU knows to pull ignition. The Knock Link is an after market accessory to give owners visual warning of DET or engine noise and utilises its own completely separate sensor.

 

Thanks, but the question is what does the standard knock sensor look like, and how does it work (how does it detect knock)?

 

It looks much the same as a Knock Link sensor.
They all work on the same principle.
Basically they are microphones designed to pick up a particular frequency.
In the case of the OE knock sensor it sends a signal to the ECU which pulls ignition timing.