Wiring diagram question

[Ken57]

I could not find the answer to this anywhere. Looking at the wiring diagram on the fsm, I see about 6 or 7 circuits "encased in dashes" and within this encasement is a white and/or black wire. Also there looks like another black wire at the beginning and/or end of this encasement. Does this mean at some point in the wiring curcit the black wire connects to the white wire?
I'm clueless?
Thanks

[Hijacker]

Those are shielded wires. The shielding is then grounded somewhere. You usually see them on circuits that need to cut down on EM interference (like the MAF or O2 sensors)

[Ken57]

Thanks Hijacker,

You are correct, it looks like both the MAF and O2 sensor are also shielded. So does the ground wire physically connect to the circuit wire in question? Please forgive me as I know very little about electronics.

My problem is that my knock sensor error code 34 keeps coming on. If I clear the ecu it goes away for a while and then comes back. I replaced the knock sensor but the problem is definately a wiring issue. Can a shielded wire be replaced with a regular wire?

[Hijacker]

According to my service manual, the Knock sensor shielding should ground to the engine ground near the throttle body.

Where on the wiring it shifts to that ground, I have no clue. TBH, I haven't dug around inside a wiring harness to find out.

I have replaced sections of shielding with unshielded in the past without throwing codes. The knock sensor SHOULDN'T give you issues if you were to run an unshielded wire, but instead of doing all that, you could just take a look to see if there's something that has cut/rubbed that wire on your harness. I would also do a continuity test of the circuit to see if there's a disconnect somewhere along the way (ties into having the harness cut or rubbed).

[Ken57]

Yes I can see from the diagram that the ground wire ends at engine ground F20. I tested the black ground wire from the F36 connector (which I had to snip because it was completely crumbling) to F20 and there is continuity.

However, I have an intermittent continuity problem from the white wire at F36 to the #27 terminal to the ecu. So somewhere there is a short, it must be coming from inside the engine compartment, my wiring harness is original and pretty cooked up. I may just order a new one.

[Hijacker]

More than likely, there's a bit of melted nastiness somewhere in there, or the sheathing of the sensor wire itself is coming apart like how you described the ground. Fix that wire, and you should be golden