Knock control settings

[wayne rowberry1436215434]

I want to set up knock control on a few cars running G3 lem, I cant seem to find any info on the settings for “gain channel†and “freq channel†I assume that it is channel filtering but a little more info would be good. I have 3.25 software and cant find any descriptions on these two topics, does anyone know where I can find out more??

[ashesman]

G3 LEM does not do Knock Control.  Only high end G3 ECU's (such as LinkPlus G3, EVOLink G3, WRXLink G3 etc...)  support knock control.  You will also notice that the LEM G3 does not have a pin to wire the knock sensor to.  Help for all tuning functions is found in the PCLink online help if you want to read up on Knock Control anyway.

[wayne rowberry1436215434]

Hi there. Sorry they are link plus G3 computers, I can turn knock control on etc but I can not find any information about the above two parameters in the online help, there is information regarding all other Knock settings but nothing pertaining to “gain channel†and “freq channel†any help on this would be great… thanks..

[ashesman]

Good spotting.  I have added a section in the manual on Knock Filtering.  It will be included in the next PCLink release.  Thanks for spotting that!  anyways, here is the section that has been added (unfortunately the formatting has been stripped out ):

Filtering

   On G3 ECU's equipped with Knock Control, signal filtering is configurable.  The following adjustments are available to configure knock signal filtering:

Freq Channel - This setting sets the sensitivity of the ECU to a particular knock signal frequency range.  The following options are available:

LP Only - Knock input is sensitive to all frequencies below 7 kHz

5.5 kHz - Knock input is most sensitive to frequencies near 5.5 kHz

7.0 kHz - Knock input is most sensitive to frequencies near 7.0 kHz

9.0 kHz - Knock input is most sensitive to frequencies near 9.0 kHz

Gain Channel - This setting adjusts the overall gain of the knock circuitry amplifier.  A higher gain number will result in larger Knock Level numbers for a particular signal input.  Use this adjustment to getter a better range of Knock Level numbers.  If Knock Level numbers are reaching full scale  then reducing Gain Channel will bring them back into range.

   The required Gain Channel and Freq Channel numbers will depend on the engine type, engine capacity, knock sensor type and knock sensor location.  A  Freq Channel setting of LP Only is not often used and exists for compatibility with older ECU's.  As a general rule engines with a larger capacity require a lower Freq Channel setting.