DIY lambda probe repair

In detail: do-it-yourself lambda probe repair from a real master for the site my.housecope.com.

Many sensors are installed in the design of a modern car. Each of them is responsible for measuring a specific parameter. The data they receive is forwarded to the control unit. He, in turn, generates commands that adjust the operation of the machine to current conditions.

The most famous sensors include:

  • speed sensor,
  • temperature sensor,
  • light sensor,
  • oxygen sensor or lambda probe.

The latter will be discussed further. The lambda probe has several functions. Firstly, it improves the performance of the engine due to the correct dosage of fuel, and secondly, it reduces the harmfulness of exhaust gases. More precisely, it improves the performance of the catalyst and extends its useful life.

The design does not represent anything super complicated. It is based on two electrodes - an internal and an external one. The outer element is platinum-plated. This greatly increases its sensitivity to oxygen. The material of the inner element is zirconium.

The exhaust gases pass through the workpiece, and an external electrode records the amount of oxygen in them. The potential between the electrodes is of particular importance during the operation of the electrodes.

The device also contains a heater. Its task is to raise the temperature when the engine is cold started. All devices are divided into two types:

The first type has already been described above. In turn, a broadband device works in a completely different way. In it, the main role is played by the current during pumping. The structure itself consists of two ceramic elements - an injection and a two-point one.

Video (click to play).

As you can see, the lambda probe plays an extremely important role in the operation of the car. This is why you need to constantly monitor your engine to get the most out of your engine. Moreover, taking into account our climatic conditions and the quality of roads, this is simply necessary.

Even under ideal conditions, combustion products build up on the oxygen sensor from prolonged use and needs to be cleaned. Taking into account the fact that the cost of a new part can reach 35-40 thousand, it is better to take care of its high-quality service in advance.

Under no circumstances should mechanical cleaning techniques be used. They can significantly damage parts. The fact is that the lambda probe is covered with a thin layer of precious metals and mechanical cleaning can remove this coating.

Cleaning the lambda probe is best done with phosphoric acid. It delicately removes carbon deposits without harming the part itself. But before using it, the device must be disassembled.

Disassembly of the lambda probe must be carried out on a lathe. The fact is that the saw can easily damage the sensor and it will no longer be possible to restore it. Therefore, you will need thin incisors. With their help, you need to cut off the protective cap and remove the wiring.

After the lambda probe is disassembled, find the ceramic rod. It is on it that you need to apply a thin layer of phosphoric acid. A regular paint brush works best for this task.

A high level of contamination is indicated by a black or brown color of the rod. But as soon as the rod turns gray, you will have to stop cleaning the lambda probe.

Phosphoric acid does not immediately act on dirt. She needs at least 20 minutes. After that, for further cleaning, you will need to rinse the lambda probe with plain water. Also, the part is dried before assembly.

In order to weld the cap you removed in place, you need to use argon welding. If you do not have the appropriate equipment, the lambda probe is cleaned with the cap put on.

To make it possible to clean the lambda probe with a cap, it is necessary to make two small windows in it. A simple file is perfect for this task. Then just rinse the part without disassembling it.

At the end of cleaning, the device is put back in place. But before you can finish cleaning it, you need to do a control test. To do this, you need a computer scanner.

The part plays an extremely important role in the operation of the engine. It allows you to increase its performance due to the correct dosing of air. Unsurprisingly, its unstable performance is bad for the overall dynamism. Despite this, cleaning is an extreme method that is used only when serious failures are detected.

The lambda probe, also known as the oxygen sensor, allows you to estimate the amount of free oxygen remaining in the exhaust gases. Its readings allow the ECU to correct the composition of the mixture. Oxygen sensor malfunctions may cause the engine to malfunction. Before replacing it, try do it yourself oxygen sensor repair.

First, let's figure out where and what is a lambda probe for?:

Hello everyone! My name is Mikhail, now I'll tell you a story about how I managed to exchange a dvenashka for a 2010 Camry. It all started with the fact that I was wildly annoyed by the breakdowns of the two, like nothing serious broke down, but the little things, damn it, so many things that really started to enrage. Here the idea was born that it was time to change the car to a foreign car. The choice fell on the tayet Camry of the tenths.

The sensor reacts to the difference between the oxygen level in the exhaust gas and in the atmosphere, producing a corresponding potential difference at the outlet. Since a certain amount of oxygen must be present in the exhaust for normal afterburning of CO and CH on the catalyst, for more accurate regulation, use second oxygen sensor, which is located behind the catalyst.

The first 5-7 minutes after starting the engine, the ECU corrects the composition of the mixture based on the readings of other sensors and according to the averaged parameters. After this time, when the oxygen sensor has warmed up to operating temperature, then the ECU connects its parameters to the general calculation formula.

Oxygen sensor error could be caused by a malfunction of the heating circuit. As a result, the sensor will not have time to warm up in the allotted time, which means that incorrect oxygen sensor signals... The fuel mixture will be inappropriate, which negatively affects the operation of the engine (high fuel consumption, idling speed floats, the car does not drive). As soon as the oxygen sensor warms up to operating temperature, then all symptoms disappear.

Read also:  DIY kamaz car repair

Resource of the oxygen sensor VAZ can reach 100-150 thousand km., but the service replacement of the oxygen sensor in the top ten should take place in the range of 60-80 thousand km.

A common cause of malfunctions is carbon deposits, which interfere with oxygen capture and thus distort the output signal.
Image - DIY lambda probe repair

Therefore, to restore oxygen sensor you need to clean the platinum electrodes on the ceramic rod from carbon deposits.
It is impossible to clean carbon deposits by mechanical means, since this method will damage the metal spraying. It remains only to resort to the help of chemistry.

We open the sensor, for this we saw off first the first and then the second protective caps. Objective: to reach a white ceramic rod with carbon deposits of the same color.
Image - DIY lambda probe repair


Phosphoric acid is required to clean the sensor rod from carbon deposits, which may be part of the rust converter. Before using cleaning products, make sure they do not leave behind a protective layer.

Image - DIY lambda probe repair

We immerse our sensor in the cleaner for 20 minutes. During this time, the liquid will begin to grow cloudy, and the carbon deposits will go off (use of a soft brush is allowed).

Heating also allows you to get rid of carbon deposits, especially if you sharply cool the rod after heating. The temperature difference forces the soot to crack and fall off like a shell.
Image - DIY lambda probe repair

We heat the ceramic rod a couple of times over an open fire.

After cleaning, we grab the caps on several points of the semi-automatic kempi welding.

Oxygen sensor VAZ 2110, as sensors of foreign cars have a similar structure, therefore such cleaning the lambda probe suitable for every car enthusiast.

In order to get rid of constant fines from cameras, many of our readers successfully use Special Nano Film for numbers. Legal and 100% reliable way to protect yourself from fines. Having familiarized ourselves and carefully studying this method, we decided to offer it to you as well.

In order to get rid of constant fines from cameras, many of our readers successfully use Special Nano Film for numbers. Legal and 100% reliable way to protect yourself from fines. Having familiarized ourselves and carefully studying this method, we decided to offer it to you as well.

Did you manage to repair the oxygen sensor of the car?

All parts and assemblies of the car have their own service life. It can be long, short, but endless - never, so every element of the car needs to be replaced sooner or later. The lambda probe is no exception. Moreover, it fails, unfortunately, quite often, but it is not cheap, so it is not surprising that experienced motorists, bypassing the recommendations of the manufacturers, have found a way (and not even one) how to clean the lambda probe at home, that is, significantly reduce their costs for repairs. But first things first.

A lambda umbrella (also often called an oxygen sensor) is a special sensor-controller that measures (estimates) the amount of oxygen remaining in the unburned fuel mixture (exhaust gases) of a car, compares it with nominal values ​​and sends the data obtained as a result of this comparison to control unit (CU) fuel system. The control unit, in turn, in order to optimize the composition of the combustible mixture, increases or decreases the volume of fuel supplied to the combustion chamber, thereby affecting the content of harmful substances in the exhaust gases, the dynamics of the car, the stability of the power plant and other characteristics.

Image - DIY lambda probe repair

Hence, it is obvious that if the oxygen sensor is faulty, that is, it sends incorrect information to the control unit, then the fuel / oxygen supply will be made with errors. As a result, the car will start to “eat” a lot, accelerate poorly, work unstably and pollute the environment (more than the accepted environmental standards allow). Such a situation can be prevented only by timely replacement of a failed sensor or cleaning it in cases where it is permissible - the sensor itself, its base are not damaged, and improper operation is provoked by contamination accumulated on it (lead deposits and soot).

The first step is to find this lambda probe. This can be done under the hood of your car in front of the catalyst. And in modern cars, two such sensors are installed - before and after the catalyst, so it is easiest to view them from the pit.

Once you find the lambda zotd (s) in your car, dismantle it (s) using a key of a suitable size.

Then move on to cleaning.

This method could be called one of the simplest and fastest, if not for the need for full / partial access to the ceramic-platinum base of the device, hidden behind a protective metal cap, which is not so easy to remove, given the impossibility of working with a hacksaw on metal , as it can damage the working base.What to do? - Use a lathe for this purpose: use a lathe at the very base of the lambda probe to cut off the protective cap near the thread with a cutter.

If you don't have such a machine, you can try using a file. Of course, you won't be able to remove the protective cap with it, but making windows (5 mm holes) in it is easy.

Image - DIY lambda probe repair

So, when access to the working rod of the lambda probe is provided, you can proceed directly to the procedure for cleaning it.

To do this, take at least 100 ml of phosphoric acid (its analogue: rust converter, flux / acid for soldering, etc.), pour it into a small glass container (glass, jar, glass, etc.), and then lower the core there clogged parts.

Image - DIY lambda probe repair

IMPORTANT: the entire device must not be immersed in phosphoric acid!

Wait 15-20 minutes, rinse the base of the part with clean water, leave to dry completely. If necessary, repeat the procedure until the black-brown core is metallic again.

Read also:  Chainsaw storm repair do it yourself

If you did not succeed in cleaning the lambda probe in this way either from the second or the third attempt, try increasing the effect of an aggressive liquid with a brush: constantly wetting and smearing the base, you will very soon notice how the dirt will begin to disappear, returning the parts to their original shine.

By the way, if the work will be carried out on the lambda probe with the protective cap removed, then instead of a brush, you can use something larger, for example, an old toothbrush.

At the end of the cleaning work, it is again recommended to rinse the oxygen sensor thoroughly with clean water and dry it thoroughly.

If the cap was removed, then before installing the part, it is returned to its place using argon welding.

When applying this method, you need to remember:

  • orthophosphoric acid (and its analogs including) is a dangerous chemical, therefore it is necessary to work with them, observing all safety rules and excluding its contact with the eyes and inside the body;
  • if the lambda probe is heavily clogged, then the named 15-20 minutes for its complete cleaning may not be enough, therefore, in especially advanced cases, the time of exposure to the acid on the core should be increased to 1-3 hours, and sometimes the whole night (at least 8 hours) ;
  • to check the effectiveness of such repairs, as a rule, it takes some time, only it will enable the driver to evaluate the "behavior" of the car and measure the fuel consumption, the exception is the Check Engine error lit up on the instrument panel, it is an indisputable sign that you will reanimate a clogged lambda probe failed;
  • if in your car the protective cap of the oxygen sensor has a double shell (two layers), most likely you will not be able to cut it with a file, so the only way to clean the core of such a lambda probe is to soak it in acid together with a protective element.

To implement it, you will need the same phosphoric acid and a gas burner or stove. If the choice falls on the latter, it is better to use the smallest burner (it will be more convenient): remove the lid from it, turn it over and put it, slightly shifting to the side, so that it protects (closes) the gas pipe from possible acid ingress there.

Then everything is simple: light a fire, dip the oxygen sensor core in acid and heat thoroughly over this fire. When the acid starts to boil and splatter, a blue-green salt will start to show through on the surface of the sensor.

Wait until the aggressive liquid boils down completely, rinse the part with clean water, dip it again in phosphoric acid and on fire ... - repeat these steps until the lambda probe shines clean (in our case, it took about 15 minutes). Before installation, the threads of the oxygen sensor should be lubricated with graphite grease (so that it does not burn).

Only then can the part be returned to its place.

Image - DIY lambda probe repair

As practice shows, the oxygen sensor, free from soot and soot, begins to work correctly again only in 1-2 percent of cases, so it is not worthwhile to rely heavily on the methods described above, cleaning the lambda probe at home with your own hands, especially if the mileage exceeds 100 thousand kilometers, however, in order to save your budget, it is still worth trying to revive this device.