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Sensor ground vs ground question

EFI Wiring Fundamentals

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I'm building a harness on my 99 Miata, currently have the OEM harness apart and planning my harness, one thing I noticed is that the factory cam, crank, and knock sensors/shield ground aren't using a sensor ground from the ECU. From the ECU one of the 16awg grounds is spliced into multiple smaller grounds that go to the above mentioned sensors as well as MAF, and OEM o2 shields and then it grounds at the front of the engine.

I am running shielded Tefzel for cam, crank, and knock. Should I terminate the shield and ground it to the same location as OEM but run the ground wire to a sensor ground from the ECU? Thanks.

Usually shields are grounded to chassis ground. You might want to double check with your ECU manufacturer (if you are running standalone), but I can confirm that ECU Master tells you to ground shield to chassis ground!

Ok I think I had the cam and crank mixed up as they aren't shielded from the factory on the NB1 at least, I was looking at the factory o2 shielded wires.

So that leaves me with the question on the knock sensor. The factory setup has the sensor ground and shield both grounding to the chassis, I am going to be using a 2 wire Bosch sensor with a shielded 2 wire. From my knowledge I should ground the shield to the chasis close to the ECU, then one wire to signal on ECU and the 2nd wire should go to a sensor ground from the ECU as well. Does that sound right? Thank you

Yup. To sum it up :

1 pin of the sensor to knock sensor input

1 pin of the sensor to sensor ground

Then ground the shield of the cable to chassis ground.

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