Harness wire specifications question

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dmage

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Hi folks

I keep getting the p0137 code for bad o2 sensor (bank 1, sensor 2). I swapped the post-cat sensor, it looked pretty beat up but I still get the code with the new sensor. I looked around and I'm pretty certain the wiring harness is in bad shape in that area, must have been laying on the exhaust and melted a bit (maybe). Does anyone have recommendation on the type of wire/gauge/spec to use replacing those wires? I saw some wiring diagrams and they had gauge but I couldn't make sense of it. Diagrams would say things like 1 gauge, or 0.8 gauge but I'm used to 16, 18 gauge.

Thanks in advance!
 

PlayingWithTBI

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Schurkey

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The O2 sensor gets it's supply of fresh atmospheric gasses (air) through the gap between the conductor and the insulation of the wire harness. If the harness is damaged, you may have destroyed the ability of the sensor to get it's reference for atmospheric O2.

As said...the brain trust at gm uses metric measurements for wire gauge. Thanks, gm. [Sarcasm] Really appreciate that touch, 'cause every parts store in North America has metric-sized wire in stock and ready for sale in all sorts of colors. [/Sarcasm]

Dirtbags.
 

xXxPARAGONxXx

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Hi folks

I keep getting the p0137 code for bad o2 sensor (bank 1, sensor 2). I swapped the post-cat sensor, it looked pretty beat up but I still get the code with the new sensor. I looked around and I'm pretty certain the wiring harness is in bad shape in that area, must have been laying on the exhaust and melted a bit (maybe). Does anyone have recommendation on the type of wire/gauge/spec to use replacing those wires? I saw some wiring diagrams and they had gauge but I couldn't make sense of it. Diagrams would say things like 1 gauge, or 0.8 gauge but I'm used to 16, 18 gauge.

Thanks in advance!

The service manual uses square mm rather than gauge for wire size specifications. Same information can also be found in page 19 (bottom right corner) of the attachment.

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  • Kent-Moore J-38125-620B Terminal Repair Booklet.pdf
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eran tomer

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The O2 sensor gets it's supply of fresh atmospheric gasses (air) through the gap between the conductor and the insulation of the wire harness. If the harness is damaged, you may have destroyed the ability of the sensor to get it's reference for atmospheric O2.

interesting, never knew that.
do you mean the air enters from here? or elsewhere?
 

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PlayingWithTBI

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do you mean the air enters from here? or elsewhere?
Yes, through the outside air chamber. Here's a cross section of one to give you an idea of how they work. It compares the difference between outside O2 content with exhaust O2 content.
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xXxPARAGONxXx

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why the manual says not to weld a damaged wire or connector?
Do you mean solder?

The standard means of connecting two broken wires together is to crimp the wires in a splice clip, and then place solder into the hole on the splice clip. Soldering alone is not the prescribed repair method.

As far as connectors — those are the plastic ends that the wire terminals enter.
 
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