How does the knock sensor work?? I know how to hit the housing near it, and watch the timing retard. The question is how does it work. Frequency? What happens b/t the sensor and the control unit????

 

the knock sensor is basically a microphone tuned to a specific frequency, and it generates a voltage, after that it gets kinda murky though, doesn't it? i dunno why they have that extra box. heres some reading for you

http://www.vishnutuning.com/bb/showt...t=knock+sensor

mike

 

j9fd3s......thank you for the reply. By the way, you might have seen my post today about the fcd's on series five and series four. Can you tell me what the difference is in the wiring b/t the two. I have no series five schematic and do not trust the Haynes manual. Is the wiring the same b/t the two? Or is the plug different?? This came up in a discussion about why RB sells one for the series four and a different part for the series five. Haynes manual shows the wire colors the same and going to the same input/output. Can't trust a Haynes though. Too much gibberish.

 

i think the only difference between s4 and s5 is that the s4 sensor has 5v, signal, ground, and 12v, while the s5 is just like any other map sensor (5v, signal, and ground). rb may also have a different value for the fuel cut between the 2, but thats just conjecture on my part.

mike