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Detecting Knock with an AEM FIC

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HP, I have a Porsche 996 with a single turbo, and an AEM FIC 8. Could I use one of the analog inputs to measure the voltage from the knock sensor to detect knock?

Thanks, Ben

You're unlikely to get anything useful by just logging the raw voltage from the knock sensor. Ideally you'd want to run the knock signal through a digital signal processor so that you can focus on the specific frequencies of knock. This helps improve the signal to noise ratio. You'll also find that the voltage level increases with engine rpm so you really need to be able to compare the signal level to a threshold to gain an idea of whether the level may be dangerous. For example a level that is totally acceptable at 7000 rpm is likely to be serious detonation at 3000 rpm.

I'd recommend a proper audio knock system personally.

Makes perfect sense. I never thought about the total noise factor and being able to differentiate the frequencies between engine noise and knock. I hear ya, knock ears are the way to go.

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