Knock sensor testing without running engine

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aidandj
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Knock sensor testing without running engine

Post by aidandj »

Is there any way to see a readout of the knock sensor data without running the engine. My motor is at the machine shop still and i want to test out my knock sensor wiring before I wrap it all up. Is there any way to output just raw data?

MS3/3x. MS3 knock module.
benckj
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Re: Knock sensor testing without running engine

Post by benckj »

As the sensor is simply a piezo resistor you could place it against any machinery to detect a frequency or sound. It won't be accurate to adjust window or sensitivity but may give enough output to tell if it's responding. Trouble is I doubt if MS would display waveform as it only reacts to a threshold vs rpm. Could you attach to another engine block for testing?

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aidandj
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Re: Knock sensor testing without running engine

Post by aidandj »

It just reads zero. I'm wondering if thats because the engine isn't running.
Yves
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Re: Knock sensor testing without running engine

Post by Yves »

tap the block lightly with a hammer. Should react.
aidandj
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Re: Knock sensor testing without running engine

Post by aidandj »

So it should react even with the engine not running?
Matt Cramer
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Re: Knock sensor testing without running engine

Post by Matt Cramer »

MS3 knock sensing only listens during a specified crank angle. You'd have to send it a simulated RPM signal, possibly with a JimStim.
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aidandj
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Re: Knock sensor testing without running engine

Post by aidandj »

Ok that was my worry. Thanks for clearing that up Matt.
Yves
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Re: Knock sensor testing without running engine

Post by Yves »

aidandj wrote:So it should react even with the engine not running?
Yes, but I should have mentioned that you need to listen to it with a headphone.
aidandj
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Re: Knock sensor testing without running engine

Post by aidandj »

I don't have headphones. Its an MS3 knock module. I trust that the knock sensor is working, but want to check the knock module and subsequent wiring.
Yves
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Re: Knock sensor testing without running engine

Post by Yves »

get the engine running en then tap the block slightly with a hammer in the area where the sensor is. And don't destroy anything of course.
aidandj
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Re: Knock sensor testing without running engine

Post by aidandj »

Yes I know. My question was whether or not I could do it with the engine not running.
joefus25
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Re: Knock sensor testing without running engine

Post by joefus25 »

Is there an answer to this? I am also wondering the same and have hunted around to no avail. At least able to log it to show that the knock signal pulls low or whatever?
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jsmcortina
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Re: Knock sensor testing without running engine

Post by jsmcortina »

See Matt's answer.

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