Page 1 of 1

Adjust Knock Sensor Sensitivity?

Posted: Wed Jun 23, 2010 7:39 am
by HermaN
Just wondering, if you have a car that is logging knock, but there is nothing being heard via det-cans, can the sensitivity of the sensor be altered, so that is only pick up knock when you can actually hear it on det-cans?

If so, how?

Cheers!

Re: Adjust Knock Sensor Sensitivity?

Posted: Wed Jun 23, 2010 9:36 am
by Matt
There are knock counts in various ECUs which the limits could potentially be adjusted (would be on per an ECU basis depending on how nissan implemented it). However the sensitivity of the board itself that generates the knock pulses from input frequencies cannot be adjusted

Re: Adjust Knock Sensor Sensitivity?

Posted: Wed Jun 23, 2010 7:43 pm
by KillerB
Is it not possible to insert some kind of attenuator in the piezo signal?

Perhaps a resistive divider or capacitive coupling?

Re: Adjust Knock Sensor Sensitivity?

Posted: Thu Jun 24, 2010 2:01 pm
by Matt
you could try, but thats beyond my knowledge

Re: Adjust Knock Sensor Sensitivity?

Posted: Fri Jun 25, 2010 6:45 am
by HermaN
Cheers for the info guys. So can't be done via NIStune then. Might look into what KillerB suggested. 8)

Re: Adjust Knock Sensor Sensitivity?

Posted: Wed Sep 22, 2010 7:53 pm
by chris2712au
if you filter out the knock frequency it will not detect knock period.. the only thing is to increase the knock count threshold.. cause that is the sensitivity.. how many times the knock is detected.. and how long it is detected for..

Re: Adjust Knock Sensor Sensitivity?

Posted: Thu Sep 23, 2010 4:38 am
by KillerB
if you filter out all the knock frequencies, then yes you wont detect it any more. But thats different from attenuating the signal.