General upstream o2 sensor issues

[TimF]

Noticed on link my brothers front o2 is not getting a signal. Initially I thought it was a bad sensor, until I noticed some tape around the harness side of the plug. The 4 wires look fine but I noticed a bare wire that seems to wrap around them all? What is that for or from?

* we are cleaning up PO rigged fixes and issues this was not our doing. *

 

[Vegas Smith]

You're probably referring to the "shielded" signal and ground wire for the o2 sensor. The weird wiring is the shield. I'm uncertain of it's purpose but it's presumably to keep the signal clean amongst all the other wires.

 

[TimF]

I see. So with the wires still intact it should still be sensors itself then