Are all knock sensors melted?
#1
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I'm building a 04 and sensor looked like it overheated and the epoxy type substance had driped out of it. Wanting to keep stock Mazda sensors I ordered a used one and it came in looking worse than the one it had. This happen to them? Are they still good??
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So long as neither lead is shorted to ground (via the housing), and the sensor element is still rigidly connected to it, I see no reason why a partially-melted sensor wouldn't continue to function.
In theory, you should be able to test it by whacking the intake manifold with a hammer while watching the pulley with a timing light. Never tried this myself.
In theory, you should be able to test it by whacking the intake manifold with a hammer while watching the pulley with a timing light. Never tried this myself.
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Not really. It's a piezoelectric sensor, so it's not like sticking an ohmmeter across it is going to do any good.
If you have access to an oscilloscope, you could measure the voltage across it (maybe 5-10mv/div) while you bang on it with a hammer.
If you have access to an oscilloscope, you could measure the voltage across it (maybe 5-10mv/div) while you bang on it with a hammer.
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AIUI, a knock sensor is basically a specialized microphone. I *think* this means you could do a basic function test by hooking it to the audio in on a PC, tapping it with a hammer while recording, and then play back the sound file to see if you can hear the "knocks".
(disclaimer: I'm a software guy, not a hardware one, so this might blow up your computer, set your house on fire, and trigger the collapse of the false vacuum thus ending the universe as we know it.)
--Ian
(disclaimer: I'm a software guy, not a hardware one, so this might blow up your computer, set your house on fire, and trigger the collapse of the false vacuum thus ending the universe as we know it.)
--Ian
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the sensor will not melt. the dollop of resin that does melt is the stuff that simply holds the wire in place. Have you ever even looked at the sensor in person?
I know you're enthusiastic about wrenching on your car, and that's good, but it seems like you're just jumping into topics completely clueless and starting conversations about fixing problems that are just not there instead of focusing on issues that actually need attention.
So to re-cap: oem nb knock sensor is a perfectly good solution for knock detection on our cars. Nothing "better" needed. The resin melting doesn't affect anything or you'd see hundreds of people replacing their knock sensors every 5 years and/or complaining about it.
So basically, this is not a problem
I know you're enthusiastic about wrenching on your car, and that's good, but it seems like you're just jumping into topics completely clueless and starting conversations about fixing problems that are just not there instead of focusing on issues that actually need attention.
So to re-cap: oem nb knock sensor is a perfectly good solution for knock detection on our cars. Nothing "better" needed. The resin melting doesn't affect anything or you'd see hundreds of people replacing their knock sensors every 5 years and/or complaining about it.
So basically, this is not a problem
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