Wire soldering problem
Burning Brakes
Joined: Dec 2007
Posts: 952
Likes: 0
I purchased a universal four wire O2 sensor for m '81. This has no connector on the end. It did come with four crimp butt connectors and shrink sleeving, with instructions to cut the connector off the original O2 sensor along with as much wire as needed, crimp to the new one and install into exhaust.
There was no mention of maintaining any kind of gap for reference air.
This would be using the same type of wire..more or less. I just used about 10" of copper wire of the same gauge. True each joint increased resistance which will affect the O2 sensor output, by just how much...depends upon the drive current from the O2 sensor...which I doubt is very much...all low level. I think that each connection adds no more than 0.1 ohms at the most...not something my Fluke DMM is going to measure. Worst case is that I may run a bit lean due to the small voltage drop across these connections which again depends upon the current output from the O2 sensor.
Right now though...getting this engine to run leaner would be nice, very nice.
There was no mention of maintaining any kind of gap for reference air.
This would be using the same type of wire..more or less. I just used about 10" of copper wire of the same gauge. True each joint increased resistance which will affect the O2 sensor output, by just how much...depends upon the drive current from the O2 sensor...which I doubt is very much...all low level. I think that each connection adds no more than 0.1 ohms at the most...not something my Fluke DMM is going to measure. Worst case is that I may run a bit lean due to the small voltage drop across these connections which again depends upon the current output from the O2 sensor.
Right now though...getting this engine to run leaner would be nice, very nice.
I DO know that oxygen sensors are pigtailed with Teflon insulation, and sheathed in high temp woven glass. I do NOT know if it is Platinum Coated like the sensor itself.
I would use the stock sensor, and a "Ready made" extension", but go ahead and try it.
Racer
Joined: Jul 2005
Posts: 499
Likes: 1
From: Winnipeg Manitoba
The info I've found says that the oxygern sensor creates a voltage by comparing the oxygen in the exhaust to the oxygen in the outside air.
"Older style oxygen sensors actually have a small hole in the body shell so air can enter the sensor.
Newer style O2 sensors "breathe" through their wire connectors and have no vent hole.
The space between the insulation and wire provides enough room for air to seep into the sensor.
For this reason, grease should never be used on O2 sensor connectors because it can block the flow of air. "
This would imply that oxygen sensor wire is in fact "special".
1) Its probably not copper wire. If air can travel down the insulation,
water can too. Water + Copper = corrosion and restricted venting.
At the very least, its plated with something that will not corrode.
2) Soldering on the end of the wire may not be a very good idea as the insulation could melt and restrict the air venting.
Crimping would be better.
3) Shrinkwrap may not be a very good idea as it could also restrict the air venting.
The shrink wrap with the built in sealant would be really bad.
So to answer the original post...Although the wire is special,
Its not due to its conductive properties or any thermal-electric effects.
Its due to air venting which occurs at the connector.
Extending the wires on the other side of the connector with copper should be fine.
http://http://www.aa1car.com/library/o2sensor.htm
http://http://www.turbobricks.com/re.../O2sensors.pdf
"Older style oxygen sensors actually have a small hole in the body shell so air can enter the sensor.
Newer style O2 sensors "breathe" through their wire connectors and have no vent hole.
The space between the insulation and wire provides enough room for air to seep into the sensor.
For this reason, grease should never be used on O2 sensor connectors because it can block the flow of air. "
This would imply that oxygen sensor wire is in fact "special".
1) Its probably not copper wire. If air can travel down the insulation,
water can too. Water + Copper = corrosion and restricted venting.
At the very least, its plated with something that will not corrode.
2) Soldering on the end of the wire may not be a very good idea as the insulation could melt and restrict the air venting.
Crimping would be better.
3) Shrinkwrap may not be a very good idea as it could also restrict the air venting.
The shrink wrap with the built in sealant would be really bad.
So to answer the original post...Although the wire is special,
Its not due to its conductive properties or any thermal-electric effects.
Its due to air venting which occurs at the connector.
Extending the wires on the other side of the connector with copper should be fine.
http://http://www.aa1car.com/library/o2sensor.htm
http://http://www.turbobricks.com/re.../O2sensors.pdf
Advanced
Joined: Jun 2008
Posts: 67
Likes: 0
To all,
Kilroy is close to being on the money. I work for a company that manufacturers oxygen sensors and most oxygen sensors today gather the reference air thru the wire.
Our recommendation is to never solder the wires and always heat shrink over them to prevent any liquids from flowing down the wiring and contaminating the air reference side of the sensor.
By the way one of the most common problems with oxygen sensors is the contamination of the air reference either from oil, coolant or water intrusion. Therefore when you replace your oxygen sensors closely inspect both the outside of the harness and the inside of the connector for liquid intrusion.
Norm
Kilroy is close to being on the money. I work for a company that manufacturers oxygen sensors and most oxygen sensors today gather the reference air thru the wire.
Our recommendation is to never solder the wires and always heat shrink over them to prevent any liquids from flowing down the wiring and contaminating the air reference side of the sensor.
By the way one of the most common problems with oxygen sensors is the contamination of the air reference either from oil, coolant or water intrusion. Therefore when you replace your oxygen sensors closely inspect both the outside of the harness and the inside of the connector for liquid intrusion.
Norm
