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In bosch’s youtube installation video dated Aug 8, 2012 it showed animation of air flow along electrical wires with the instruction: “It is critical to understand that in order for the oxygen sensor to work properly air must be drawn into the sensor through the connecting wires. Therefore you must not solder the wires together. Doing so will result in a malfunctioning sensor.” Is Bosch correct? Can air travel inside electrical wire or outside electrical wire? There are quite a few feet of wires, it is hard to believe that the air can travel that far. Also there are plenty of air can go into the sensor, why does it have to be inside the wire?
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No, not at all.
O2 sensors do reference the outside oxygen levels but they do this through a series of holes drilled into the O2’s metal body.
If you go to this page about halfway down is a cutaway of an O2 sensor.
http://autorules.blogspot.com/2012/02/o2-for-you.htmlThank you for your reply. Your linked article made sense, the hole is on the metal body. Bosch is a big company, do you think they made an mistake on their installation video? It is hard to believe it since there are many views on the video and yet, no one questioned it. At my youtube video, all current comments also sided with Bosch, you are the first one who indicated otherwise.
[quote=”Raistian77″ post=81108]No, not at all.
O2 sensors do reference the outside oxygen levels but they do this through a series of holes drilled into the O2’s metal body.
If you go to this page about halfway down is a cutaway of an O2 sensor.
http://autorules.blogspot.com/2012/02/o2-for-you.html%5B/quote%5DThere probably was some miscommunication. There can be issues with soldering certain kinds of wires, for instance they may have used wire with a considerable amount of chromium added, as pure copper might not be able to take the heat. Chrome alloy wire will not take solder. So yes, the oxygen sensor might not work if you solder to the wires, but not for the reason given.
Also some soldering irons with only a 2-wire cord and no ground can have significant voltage leaking from the power line to the tip, and that can fry a lot of electronics. Oxygen sensors are super high-impedance devices, which means that it doesn’t take much current to generate insanely high voltages. So it doesn’t take much leakage from a smarmy soldering iron to zap some things. I once killed a $600 Sony car stereo that way.
this video discussed the basic operation of the sensor, but it still does not answer the question of from where does the reference air can go into the sensor.
[quote=”EricTheCarGuy” post=81123]This video may also help.[/quote][quote=”corgllc” post=81161]this video discussed the basic operation of the sensor, but it still does not answer the question of from where does the reference air can go into the sensor.
[quote=”EricTheCarGuy” post=81123]This video may also help.[/quote][/quote]So cool that video is actually yours, neat.
Yes you are right in the video, that explanation is not only incorrect, but not feasible. Air does not travel down the length of wire on the inside of the insulation. Wire is made in a process that is designed to leave it as “air tight” as possible.
Now as to the O2.
An Oxygen sensor is basically a battery that produces voltage when the concentration of oxygen on one side of the thimble is higher than the concentration of oxygen on the other side. A rich mixture produces almost 900 milivolts and a lean mixture produces about 100 milivolts. The computer uses that voltage to determine how much fuel to give the engine so it is not too lean or too rich. The sensor uses the outside air as the high reference point, there are small holes drilled around the peremitter to allow air to freely travel to the inside of the thimble. There are other O2 designs that do not require an outside air reference, but that is because they do not generate a voltage using Zirconia like the common O2s do. The Titania sensor uses a very unique resistance based signal that can detect oxygen concentration very exactly. They also can detect O2 levels well outside the range of the Zirconia sensors which lets them find the mixture immediately rather than playing hot/cold like a standard design does.
Their universal connector is a solder-less design, so on that they are correct no soldering is needed, but not for air to travel down the wires, but for the ease of installation.
I don’t recommend “universal” designs, you are dealing with milivolts at all most zero current, ANY corrosion or bad connection will severely damage the quality of the signal going to the PCM. Every connection in a circuit adds resistance to the circuit and any resistance in the circuit means the voltage to the PCM will be lower than it should be. The computer will think the engine is running lean and add fuel to compensate. You end up with a car that has bad gas mileage that runs worse than before. And any time you have to cut into a wire, even if you reattach it perfectly you are providing a possible future problem. Not to mention if you mix up a heater 12 volt feed with the signal line you could blow the PCM>
Oxygen atoms are very small relative to the space between the strands of wire in a cable and this sensor receives it’s oxygen by that route. When you solder the sensor wire, you remove that airspace between the strands of wire, and cause the sensor to work incorrectly.
[quote=”imagine44″ post=81177]Oxygen atoms are very small relative to the space between the strands of wire in a cable and this sensor receives it’s oxygen by that route. When you solder the sensor wire, you remove that airspace between the strands of wire, and cause the sensor to work incorrectly.[/quote]
I am sorry, but that is incorrect. O2s do not work that way.
The o2 reference point uses holes drilled in the metal body, it does not rely on oxygen atoms trying to make it through a foot of wire to get to the thimble. And if that were true you would have oxidation of the metal the logic defys itself. The other proof that Boch made a mistake it that their connector (the one that “allows” oxygen to travel down the wires, is sealed with rubber seals, kinda defeates the purpose eh?
So sorry that is an incorrect statement.
Certain stranded cable will indeed pass air or fluids down it’s length. It is used in specialty industrial application for cooling among other things. On this point I am sure.
Now.. I think the OP should disassemble the sensor just to see how it’s put together.. B)
[quote=”Raistian77″ post=81237][quote=”imagine44″ post=81177]Oxygen atoms are very small relative to the space between the strands of wire in a cable and this sensor receives it’s oxygen by that route. When you solder the sensor wire, you remove that airspace between the strands of wire, and cause the sensor to work incorrectly.[/quote]
I am sorry, but that is incorrect. O2s do not work that way.
The o2 reference point uses holes drilled in the metal body, it does not rely on oxygen atoms trying to make it through a foot of wire to get to the thimble. And if that were true you would have oxidation of the metal the logic defys itself. The other proof that Boch made a mistake it that their connector (the one that “allows” oxygen to travel down the wires, is sealed with rubber seals, kinda defeates the purpose eh?
So sorry that is an incorrect statement.[/quote]
I would have no idea about industrial applications. If they use it in that environment that would be pretty cool and different. But, in automotive applications I have never seen that type of wire. Computer control systems are my specialty and in that application there would not be enough O2 going down inside a wire for the computer to reference. One of the advantages to the way a O2 sensor is designed is the ease at which outside air can get to the inner thimble, it has to be easy to allow the O2 to self calibrate to varying oxygen concentrations.
I wish I still had the two old ones that were in my scrap bin, but I took them with the rest of the metal 3 weeks ago. I cut one up last year when I went to the HS to teach O2 sensor theory and operation, but that thing is long gone.
Hmm.. It would be good to know exactly how much reference air is required for this oxygen sensor, and if that quantity could be passed through the multi-strand wire used on this sensor. Then at least we could be on our way to “Busted, Plausible or Confirmed.” 🙂
[quote=”Raistian77″ post=81303]I would have no idea about industrial applications. If they use it in that environment that would be pretty cool and different. But, in automotive applications I have never seen that type of wire. Computer control systems are my specialty and in that application there would not be enough O2 going down inside a wire for the computer to reference. One of the advantages to the way a O2 sensor is designed is the ease at which outside air can get to the inner thimble, it has to be easy to allow the O2 to self calibrate to varying oxygen concentrations.
I wish I still had the two old ones that were in my scrap bin, but I took them with the rest of the metal 3 weeks ago. I cut one up last year when I went to the HS to teach O2 sensor theory and operation, but that thing is long gone.[/quote]
http://www.boschautoparts.com/BAP_Technical_Resources%2fOxygen%20Sensors%2fThimble.pdf
It looks like the reference air is brought in at the top of the sensor where the cap screwzs on and seals to the o-ring. The air is flowed in around the wires there is a accordion boot and filter there (probably confused the team that made that video most companies actually hire actors to do their “mechanic” role and the advertising team writes out the lines).
The video claimn the air is brought in at the “special” connector but as you can see here
http://www.boschautoparts.com/BAP_Technical_Resources%2fOxygen%20Sensors%2fConnectSystem.pdf
the smartlink twist connector is sealed and would block any flow of air down a wire. Plus even they claim it is sealed.Universal Heated Sensors
Bosch Universal Heated Oxygen Sensors
are designed for ease of installation. They
feature a revolutionary Bosch patented
submersible connection system which
protects against contamination and
withstands extreme temperatures and
engine vibration.They claim not to solder the wires because it would damage the sensor (and that is pure bunk) most likely they are afraid of people incorrectly soldering the sensor and causing a return and refund.
imagine44: The amount of reference air would probably be the same as the amount of exhaust that needs to contact the sensor.
[quote=”Raistian77″ post=81318]It looks like the reference air is brought in at the top of the sensor where the cap screwzs on and seals to the o-ring. The air is flowed in around the wires there is a accordion boot and filter.[/quote]
I was thinking the same thing. The diffusion rate of air through insulated, stranded wire would be very low, like um- or mm-per-hour, effectively being neglible. There is a lot more space for air to flow through the outer jacket/tubing that encloses the individual wires.
Bosch probably patented the splicing connector, and I doubt any claim about air flowing through the wires was accepted by the patent examiner, unless they had some absolute proof verifying the claim.
[quote=”Hanneman” post=81345]imagine44: The amount of reference air would probably be the same as the amount of exhaust that needs to contact the sensor.
[quote=”Raistian77″ post=81318]It looks like the reference air is brought in at the top of the sensor where the cap screwzs on and seals to the o-ring. The air is flowed in around the wires there is a accordion boot and filter.[/quote]
I was thinking the same thing. The diffusion rate of air through insulated, stranded wire would be very low, like um- or mm-per-hour, effectively being neglible. There is a lot more space for air to flow through the outer jacket/tubing that encloses the individual wires.
Bosch probably patented the splicing connector, and I doubt any claim about air flowing through the wires was accepted by the patent examiner, unless they had some absolute proof verifying the claim.[/quote]
That exactly what I was thinking.
It is not the first time I have seen a video tutorial that had a glaring error in it.
Plus Bosch has always had a….uh…..well..pseudoscience side to it. Bosch plus 4 and plus 2 plugs are a gimmick and most techs know a set of those goofy plugs will cause drive-abilty problems. Bosch relies on the DIYer market to buy that crap because they know, no shop is going to recommend them.
That universal Bosch O2 sensor is a DIYer gimmick and Bosch knows that, they don’t market that sensor to techs because they know we will buy the OEM match Bosch sensor. You know why they push that damn thing? To reduce comebacks and restocks. See almost all 4 wire zirconia O2s are identical for the most part minus the connector. So they sell the harder to make direct fit to us techs who are less likely to order the wrong sensor or to less likely to make an incorrect diagnosis and sell the “universal” to DIYers that are more likely to order the wrong direct fit and more likely to start every diagnosis with “replace O2”. By making a replacement O2 a “splice” in, you are less likely to try and re-install your old one when you find an O2 did not fix the problem.
Its a win win for them, they save money by making one O2 and you ruin yours when you install theirs meaning you wont bring it back.
sell the “universal” to DIYers that are more likely to order the wrong direct fit and more likely to start every diagnosis with “replace O2”
BTW that was not an insult to DIYers. The ugly truth is that a skilled labor job is something you have to have practice and experience with to not make mistakes. Someone who only works repairing machines once in a while is more likely to make a mistake than someone who does it 8 hours a day. Plus someone who does not work in the field every day is more easily swayed to questionable solutions than someone who does this work everyday. For example Advance Auto sells a device that plugs into the cigarette lighter and is supposed to “save gas”. Funny thing is that it does, but knowing how means techs understand that the savings is about a drops worth of fuel a week. Since the product does not tell you how much fuel is saved (just hints at ti) it never technically lies (*no laws broken) and someone that might not understand the theory wont realize that it would take 100 years to pay for itself.
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