General Tech Help: Oxygen Sensor Wire Repair

[Stephen]

When I did my EFI swap last year, I had a new harness built which had a new O2 sensor wire. This left the original harness (which needed to stay for some accessories) with an unconnected O2 sensor. Because of this, my sensor light has been on. I thought, "Hey, I'll just get a Y splitter and splice the old wire and the new one."
I think I may have made a mistake. The O2 sensor wire seems to have two layers. An inner wire and an outer wire that seems to encase the inner one. Unfortunately I found this out after doing the big snip. I spliced everything together, but now the engine occasionally seems to sputter like its getting an incorrect fuel mixture.
Does anyone know how to fix this mistake? Any thoughts are appreciated.

 

[4x4_Welder]

The outer layer is a shield, like a co-ax cable. The signal is also low voltage, between .5 and 1.5v, so you need to solder it, if you haven't. I use solder link connectors with good results.
One way to fix it is to peel the shield back about 1" on either side, solder and shrink wrap the signal wire, wrap a piece of tin foil around that, making sure it contacts the shield on both ends to ground it properly, and put a piece of heat shrink tube over the whole thing repair area.
As far as turning off the sensor light, you should either rewire it so it's actually your "check engine" light if you don't have one, or just pull the bulb. Since the O2 generates voltage to create a signal, there's a chance the stock computer will alter the signal enough to provide incorrect feedback to the computer that's actually running the engine, causing all sorts of issues.

 

[Stephen]

The outer layer is a shield, like a co-ax cable. The signal is also low voltage, between .5 and 1.5v, so you need to solder it, if you haven't. I use solder link connectors with good results.
One way to fix it is to peel the shield back about 1" on either side, solder and shrink wrap the signal wire, wrap a piece of tin foil around that, making sure it contacts the shield on both ends to ground it properly, and put a piece of heat shrink tube over the whole thing repair area.
As far as turning off the sensor light, you should either rewire it so it's actually your "check engine" light if you don't have one, or just pull the bulb. Since the O2 generates voltage to create a signal, there's a chance the stock computer will alter the signal enough to provide incorrect feedback to the computer that's actually running the engine, causing all sorts of issues.

Worked perfectly, thank you.