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knock sensor interswaps?


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Now, I recall why I asked - not entirely due to laziness. There is a limitation to what the manuals reveal once wires go inside the KCM of Series I

 

It is two wires from sensor to box

 

Need to add in words of description AND understand piezo, but its a bit like an O2 sensor that produces a small Voltage

O2 sensors can be as simple as a single wire, as can be most modern knock sensors ?

 

That would make one wire off the sensor an earth from the knock box, the other to carry Votage produced by the piezo.

 

I do klnow that normal running the Series I produces 1.7V out of the KCM test wire and ramps up as high as 4.5V but doubt this is produced by the knock sensor piezo itself, but doubt is with little knowledge

 

Now, think back to piezo bbq igniters, hws igniters, mozzy bite calmer downer gadgets

 

Maybe it does produce such Votages or the KCM builds it up to an automotive computer ECU level

 

At the moment I do not have a working Series I KCM circuit to work with.

May just have to fit it up to my MONGREL, tap into and monitor both wires from the white two wire baby

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  • 2 weeks later...

where have all experts gone then ?

 

I ordered one genuine(leaving a testicle as a deposit - Rock wanted both!! )

 

Only live once - or twice. Rather splurge now and get genuine, tinker later with cheap after market or new style

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Oh yeah ask away. I was wondering in case no one replied as it’s probably an uncommon need and situation.

 

The few I’ve had fail I just swap in another use one laying around. Ask someone to mail you two of them or one of each or two of each and Have them also mail you a pigtail for it so can you can make an adapter for yours?

 

I would think it’s easier to install a 2 wire into a 1 rather than the other way around.

 

FSM would show where those wires lead and what they’re used for.

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Yeah, Ido...FSM shows wires leading into a box of circuitry.

 

I will liely make up a shielded connection, T in a test wire at same time sso I can monitor things. I have an EJ knock sensor or two, maybe even a Ford six one as well. Someone tells me if you see an EJ knock sensor with a crack it is a sign its been overheated. I know I have a cracked one.

 

I am also thinking I will fit a knock sensor dizzy to my NA running 22 DBTDC @ 800 rpm idle as just starting to hear it ping at high revs in 3rd of five gears. The box is already in the car for turbo engine. Or braze up the ends of the advance slots in the dizzy for some old school tuning :D

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that's awesome you're willing to try that, good idea. 

 

Someone tells me if you see an EJ knock sensor with a crack it is a sign its been overheated. I know I have a cracked one. 

 

nah, they crack all the time.  by far most common EJ sensor failure for all 20+ years of the existence of that engine.  i have no idea how many i've seen crack. 

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