Audio Knock Detection Question?

I made an audio knock detection device based on this article:

https://uprev.com/documentation/Knock%20Listen%20Device.pdf

I made some changes to the design on how it interfaces with the knock sensor because I'm only tuning Subarus at the moment I wanted to be able to plug the audio knock device in without having to splice into someone else's wiring. I took a male and female knock sensor connector and made an extension which the aux wire splices into. that way I just unplug the sensor and plug it into this extension. and i want to keep the factory knock detection working while I'm tuning.

It worked great, with one exception. I got a P0327 code for knock sensor low input. Im wondering if this is normal when using audio knock devices.

Im wondering if i can either ignore it or disable that code while I'm using the device, or if it will put my car in limp mode, or make the factory knock system not function correctly.

Any advice is appreciated, never used a Audio knock system before so just looking for some conformation.

Hello, unfortunately, the knock sensor cannot be shared with the car and your unit. I suggest using another knock sensor and fitting that separately on the engine,

Regards Ross

I followed the exact article, and it works great. Except I did use my own separate sensor instead of sharing the stock one.

Here's a good sensor to use Bosch 0261231188

Alright thank you guys!

Thats a bummer, it would be nice if I could just use the stock sensor, but I should have known its never that easy lol.

@wedge905 how did you get power to the sensor with your design?

Knock sensors are passive, they don't need power.

The signal is just really weak on its own, that's why you need an amplifier to hear them.