951gashog

Why do some suggest that soldering O2 sensor signal leads should have any effect what so all on its tenth-of-a-volt output?!? And why would anyone want to solder it anyway, instead of just crimp it?? Is this some kind of dissimilar metal Seebeck voltage argument?? Thats in the microvolts regime, and is irrelevant noise compared with the tenths-voltage signal put out by the sensor. I dont see the argument here against soldering the wires (other than who would want to). As long as the connection is good, it seems irrelevant to me what form it is made in...

Bri Bro

It not the junction voltage that is the problem, it is the flow of outside air through the stranded wire. Since it requires on molecules of outside air to make the sensor work, the air flows through the wire. If you solder it, it makes a dam for the air flow.

Older O2 sensor had a small hole at the tip of the sensor but it would get plugged by oil and road grime and stop working. Supply the outside air through the wire fixed this problem.

951gashog

Hi Brian,

So youre saying air actually diffuses between wire and inside of insulation? Or does it diffuse in where 3 wires enter back of sensor, external to insulation (about the same effect as having a hole there!) Thats a long stretch of wire to get diffusion thru, talk about shorting out the conductivity of O2 partial pressure to the zirconia!!

951gashog

Okay I just walked out and looked at my new O2 sensor which I crimped on (crimps up high, near OEM plug), and the insulation is loose enough on the stranded wires to let O2 through. This is actually an argument for crimping, as it looks like the insulation to the OEM plug is sealed in there, blocking O2 throughput.

UK952

Does the cable end of the sensor get hot enough to melt solder?

Sam Lin

MUST be crimped, or soldered and the insulation cut behind the sensor. Simply soldering it will block the airflow as has been mentioned. It is not a voltage/electrical signal transfer issue.

Sam