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Hey Guys,

I've got a S2 R33, a consult cable, and the nisdatascan software. What i want to know is if it is possible to determine when a knock occurrs... the ecu error code can tell you that a knock DID occur, but how useful is that? Wouldn't it be better to know at what RPM the engine knocks? Is this possible to do in our cars, i mean, without the stethoscope and a keen set of ears?

Cheers

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Hey Guys,

I've got a S2 R33, a consult cable, and the nisdatascan software. What i want to know is if it is possible to determine when a knock occurrs... the ecu error code can tell you that a knock DID occur, but how useful is that? Wouldn't it be better to know at what RPM the engine knocks? Is this possible to do in our cars, i mean, without the stethoscope and a keen set of ears?

Cheers

the ECU error code for knock sensor doesnt tell you if a knock occurred. it tells you if it detects a fault with the knock sensor.

I have datascan and as far as i know it cannot log the knock sensor. As Pete said above, ECU error code for detonation sensor circuit just means that your det sensor circuit is showing an abnormal resistance (open circuit, dead sensor etc) and will trigger the error code.

When your car does detonate it will go into safety mode, it will not show an error code.

Have you considered an aftermarket product like a knock-link? You can read up about them on the AMEC website ( www.amecautocare.com.au ) under the electornics section.

I don't know if this applies to all Nissan's, but I do know that on the Zed the knock sensor is only monitored by the ECU up until approx 3500rpm... after that the sensor can get confused between normal engine vibration/noise and detonation and may put you into safety maps even though you're not detonating. I reckon the best way would be something like a knock-link.

theoretically if you know what memory address in the ecu that the ecu uses for whether its in safe mode or not, then you can monitor that, but im not sure its generic (location could be different for diff cars) and it will just be a yes/no, not an amount.

a knock lite or similar would probably be the best choice.

your other alternative is to get something like a Knock Link LED det display unit, which BTW we can get for you :ermm: I have one in the race car, the LEDs usually start flickering at the top of the rev range.

oh another product that is similar is the TurboXS knock lite.

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