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t3rse
04-28-2006, 07:09 PM
how can i test the knock sensor. is the sensor the ground side? or the + side? what sort of voltages should i be getting.

Russ Jerome
04-28-2006, 10:44 PM
The knock sensor is a piezoelectric sensor that generates an AC voltage signal, you cant use a DVM due to high frequency signal. You could test
it if you have a scan tool and a hammer :)

gasketmaster
04-29-2006, 12:33 AM
You could test
it if you have a scan tool and a hammer :)

+1 :D

t3rse
04-29-2006, 01:12 PM
The knock sensor is a piezoelectric sensor that generates an AC voltage signal, you cant use a DVM due to high frequency signal. You could test
it if you have a scan tool and a hammer :)
well, the problem is that i have SDS with no hook up, so the scan tool is useless. i either need to wire in the sensor to the SDS, or get a standalone knock light, or just blow my ---- up.

glhs875
04-30-2006, 07:25 AM
well, the problem is that i have SDS with no hook up, so the scan tool is useless. i either need to wire in the sensor to the SDS, or get a standalone knock light, or just blow my ---- up.

Hook a timing light up to the engine. Note where the timing mark is. Now while watching the mark with a timing light, tap lightly on or near the knock sensor. If things are working, you should be able to see timing being pulled out.

t3rse
04-30-2006, 12:35 PM
i don't think you understand. that is a good idea, but my computer doesn't read the knock sensor at all, so no matter what the sensor says, the computer doesn't care, because it's not hooked up to it, hence won't pull timing.

glhs875
04-30-2006, 12:40 PM
i don't think you understand. that is a good idea, but my computer doesn't read the knock sensor at all, so no matter what the sensor says, the computer doesn't care, because it's not hooked up to it, hence won't pull timing.

I got ya! So your wanting to maybe turn on a light or something when the knock sensor detects detonation? Which that would be a good idea!!

Russ Jerome
04-30-2006, 02:24 PM
Look to the Grand National boards for info on building your
own knock light. Will require some junkyard GM parts to build.

The timing light idea wont work unfortunatly, if it was a factory
computer it would pull timing depending on boost vs. RPM vs.
knock voltage and cylinder making the noise. It may work on
a GM vehicle but there knock sensors work backwords from ours.

t3rse
05-01-2006, 11:21 AM
good deal, thanks fellas.

David Bohrer
05-01-2006, 11:28 AM
MSD makes a knock meter that has pretty lights and audible warning. The sensitivity is adjustable and so is the volume. PN 8964 i think....

bn880
05-02-2006, 08:50 AM
Look to the Grand National boards for info on building your
own knock light. Will require some junkyard GM parts to build.

The timing light idea wont work unfortunatly, if it was a factory
computer it would pull timing depending on boost vs. RPM vs.
knock voltage and cylinder making the noise. It may work on
a GM vehicle but there knock sensors work backwords from ours.

Can you possibly provide a direct link to the thread, can't find the sucker. :confused:

t3rse
05-09-2006, 07:43 PM
http://www.turbobuick.com/forums/showthread.php?t=178629&highlight=knock+gauge

http://forums.corvetteforum.com/showthread.php?t=528523&forum_id=82&arch=1

pretty straight foward looking stuff

for more info on the esc:

pdf: http://www.turbotweak.com/Knock.pdf