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11

Lambda sensors, often referred to as oxygen sensors or O2 sensors, are the bedrock of any modern-day EFI system. Without them, fuel injection management is essentially flying blind and has to resort to other less-desirable means to determine how much air and fuel need to be mixed. Their primary role is to provide feedback to the fuel management to determine ...


9

It should hold up. It melts at around twice the temperature where water boils, which I don't think you'll ever experience in the engine bay (unless it's touching the exhaust). But the greasiness in the engine may make for a poor adhesion. BTW: I am one of those people who would rather crimp than solder.


7

No, you don't have to rely on wire colors to figure out what's what. With nothing more than a decent multimeter and premix flame (blowtorch or gas stove), a two-test sequence can reveal the identity of each wire, assuming the O2 sensor is fully-functional: Determine the heater wires This should be done first. These wires serve to heat up the O2 sensor ...


5

It is most likely that this sensor has failed. The question is why does the MIL only come on above 70mph. The answer lies not in the sensor but how and when the sensor is tested by the PCM. Every sensor (and actuator) in the engine control system is tested by the software, but not all the time. Each sensor has its own set of test entry conditions; each OEM ...


5

In the perfect world, you just slide a wrench on the O2 sensor and it comes out. Unfortunately since its located in a "hostile" environment (lots of heat, lots of water and potential corrosion underneath) it typically gets pretty stuck, though most people eventually do have success getting it off. Careful not to start stripping it with that open ended ...


4

Just to add to the other answer as I ran into this same issue, what kind of emissions do I have on my mitsubishi galant? I had this code: P0421 and I had to replace my O2 Sensor & the catalytic converter but I wasn't sure if I needed the CARB (California Air Resource Board) compliant ones or not. There is a label that identifies what type you have. I ...


3

I haven't been able to find any solid conclusions on the VW forums regarding the root cause for this behavior, but there are some clues as to what could be causing this from the diagnostic code. Fred Wilson's answer remains a distinct possibility but I struggle to reason with why the engine computer would choose to throw a code/MIL for a bad sensor on a ...


3

Lambda sensors have several different failure modes. Heater element. The heater element is a resistive material that resists electron flow thus producing heat. This is the most common cause of early failure. The resistor burns through opening the circuit. Failure of the catalyst material. Usually caused by contaminates coming from the engine. Very ...


3

There are currently two kinds of narrowband sensors used these days: titania sensors (NTK) and zirconia (Bosch). This answer only addresses the zirconia sensors which are the most common type. Referring to the diagram (which was created by Michael Handrich and shared under a Creative Commons license), the sensor is a galvanic cell that generates what's ...


3

Also, remember that MAF is a reading of the amount of air entering the engine. If you have a backflow issues (high backpressure) or even a timing issue where the valves are not opening and closing at the correct time (slack chains, jumped timing), your MAF sensor readings will reflect this as well. I know this post is late, but any who are looking into this ...


3

Root Cause: probably a couple of things Sadly, I feel that there isn't enough data here to uncover the smoking gun, but I have realized some things upon reflection that can indicate what is probably wrong with the vehicle: Question 1 If the front lambda sensor voltage is indicating rich, why is the fuel trim positive (indicating that the injector ...


3

If the catalytic convertor is truly plugged, you wouldn't be able to drive the vehicle, so this makes me wonder about the voracity of your statement. With a plugged cat, the back pressure created behind it will only let you rev the engine to around 1500-2000 rpm. I had to replace a set of heads on a pick-up truck for a guy because he continued to run the ...


2

Since this is an OBDI vehicle, there will be only one O2 sensor located where the exhaust ports all come together in the exhaust manifold.


2

There are two things which could potentially cause you issues with this. First, you don't know if it is conductive. One of the properties of anti-seize is that it maintains conductivity between the two parts. In this way it works great for spark plugs and O2 sensors. I was reading about it on Wikipedia and it was a little beyond my comprehension right now ...


2

Based on fueleconomy.gov your are getting a little better than what's expected. Comparing the less accurate old rating system to the new, it's still not as high as you were expecting, but it was higher. Compare Old and New MPG Estimates The manual transmission with the 2.0 gets the best mileage that year If you look up mpg on some sites it just ...


2

Just thought I'd bring this in to an answer to allow it to be accepted: This, while not ideal for you in this situation, is to prevent accidental connection to the wrong sensor. This solution is used in any number of applications, on ships, aircraft, even buildings - and in a car you will find many examples. It's one of the reasons I always read the manual ...


2

According to research I've done on the web, the W in WO2S11 stands for wideband, meaning it can calculate much better than a standard O2 sensor. This, I would assume, is what your car is utilizing to get its O2 reading and not the O2S11. And yes, that would be for the bank 1 sensor 1 (upstream or before cat). Your issue is not with the B1S1, though, it's ...


2

In a word? Nothing. I mean, a 4-wire O2 is going to be about the same no matter what it's made for. The connector may be different, but the guts are going to be pretty much the same. Unfortunately, you really need to know what works well with your vehicle. For instance, Bosch (from my understanding) originated the O2 sensor. Their product should be above ...


2

Solder (60/40) or any other lead-based sort has little mechanical strength. And it decreases as heat goes up. Furthermore, some of the wires used in various places don't work very well with field soldering (such as Litz wire). On the other hand many of them don't work well with mechanical fastening, ie, crimping. Depending on the wires you're working with, ...


2

Your lambda control looks absolutely fine. And consequently I don't think it is the root cause for your rough idle. Here's my reasoning: The web page linked in your question says The O2 sensor must cycle at least once per second I wouldn't take this as a hard limit for a few reasons: the Bosch Fuel Injection & Engine Management book indicates ...


1

Because this issue is speed dependent, I'm almost certain that it is related to exhaust gas temperature. Paulster2 suggested checking whether the issue happens at a lower gear. However, then the load on the engine is lower, so there are less exhaust gases. It may be the case that the issue does not happen at a lower gear, therefore. But a good idea to check ...


1

This is a normal fuel control pattern especially for idle. O2 switch patterns are not specified to look a certain way but vary greatly. They are the result of a competing set of requirements including; combustion efficiency, catalyst requirements, driver demand and regulatory requirements. The hold lean strategy seen here is a way to hold the mixture ...


1

The other answers have covered most things, but here are two points that haven't yet been mentioned. Warranty This is usually a function of the supplier rather than the manufacturer, but some places offer a lifetime guarantee. Others offer none. Physical fit How hard could it possibly be to make accurate threads? Apparently pretty hard for some ...


1

In general what do the more expensive sensors have that the cheaper ones don't? There is no functional difference; all 4-wire zirconia-based narrowbands should exhibit the following: useful voltage range 0.1 - 0.9 V stoichiometric AFR at 0.45 V low voltage = lean condition, high voltage = rich condition Certain brands may have a quicker warm-up time ...


1

Start the engine and turn on the head lights and rear screen heater then check the battery voltage, it should be 13-14 volts. If it is less than 13 volts, then your alternator is faulty. If the CEL came on while starting the engine it could be the low battery voltage that confused the ECU. It is possible that something is drawing power from the battery ...


1

I am only answering where the sensor is located.This video explains the whole procedure is nicely. Including the location and how to replace it. https://www.youtube.com/watch?v=y2vXZbFjlxI


1

Yes it will be fine...if you correctly solder it. If you dont know how to solder then i would suggest a crimp.


1

I am not there to say exactly, but would suggest they probably aren't interchangable. I'd get the one which you researched to be correct. You might be able to sell the one which you don't need on Cragslist at a reduced price. Is it possible that they intended to replace the actual O2 filter in the rear of the car? If you look at the "filter" in the ...



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