Is the knock sensor grounded to the block?

[rawavr4]

I'm putting a new engine harness in my car because my old one has wires cracking everywhere and the knock sensor wiring is weird. It has the black and white wire coming off the plug. The white wire goes to the ECU and the black wire went about 10 inches into the harness and stopped. It went into a little plastic pocket thing next to the signal wire insulator. Is that normal?

[RealMcCoy]

The wire to the sensor is a shielded wire. The black wire grounds the shield.

[rawavr4]

Do you mean the shield grounds the black wire? I'm trying to figure out the best way to wire this in from scratch.

[rawavr4]

I'm still slightly confused. Sorry. So would I ground the black wire to the shield?

[RealMcCoy]

The wire is sheilded all the way from the computer to the sensor... The black wire you see in the connector simply connects the sheild in the harness to the sheild on the sensor pigtail.

[rawavr4]

Got it. Thanks

[blindmist]

Everything is fine, just leave it alone.

[Keyan]

the knock sensor doesnt require a ground. it creates a voltage when a ping (knock) resonates from the block. the shielding prevents radio interference so the ecu can interpret the voltage correctly. the shielding NEEDS to be grounded.

[rawavr4]

So now I got everything plugged in, and I put the multimeter on the plug and both the shield and signal wire are grounded. Time to tear it back apart?

[rawavr4]

With the ECU plugged in, both the shield wire and signal wire has ground and a few ohms of resistance between each other. With the ECU unplugged, only the shield wire is grounded and there isn't any resistance between the 2 wires. Any thoughts?

[rawavr4]

Yes the datalogger shows 6-9 counts at 3000rpms, and if I gas it to 3000rpmsagain it goes away. The knock sensor is brand new oem and the ECU is reman. The shield shows a good ground and the signal wire is showing 3.9ohms to ground with the ECU plugged in.