The writing of this material was prompted by an abundance of questions on an Internet forum related to a misunderstanding (or misunderstanding) of the principle of operation of an oxygen sensor, or a lambda probe.
Oxygen sensor: from general to particular
First of all, you need to go from the general to the particular and understand the operation of the system as a whole. Only then will there be a correct understanding of the operation of this very important element of the ECM and diagnostic methods will become clear.
In order not to delve into the wilds and not overload the reader with information, I will talk about the zirconium lambda probe used on VAZ cars. Those who wish to understand more deeply can independently find and read materials about titanium sensors, about broadband oxygen sensors (SODs) and come up with methods for testing them. We will talk about the most common sensor, familiar to most diagnosticians.
Once upon a time, the oxygen sensor was just a sensitive element, without any heater. The sensor was heated by exhaust gases and took a very long time. Strict toxicity standards required the sensor to quickly enter into full-fledged work, as a result of which the lambda probe acquired a built-in heater. Therefore, the VAZ oxygen sensor has 4 outputs: two of them are a heater, one is ground, and one more is a signal.
Of all these conclusions, we are only interested in the signal one.
The shape of the voltage on it can be seen in two ways:
- scanner
- motor tester by connecting the probes and starting the recorder
The second option is preferable. Why? Because the motortester makes it possible to evaluate not only the current and peak values, but also the shape of the signal, and the rate of its change. The rate of change is just a characteristic of the health of the sensor.
So, the main thing: oxygen sensor reacts to oxygen . Not on the composition of the mixture. Not in ignition timing. Not for anything else. Only for oxygen. This must be understood for sure.
The physical principle of the sensor is described in many books on electronic engine control systems, and we will not dwell on it.
A reference voltage of 0.45 V is supplied to the sensor signal output from the ECU. To be completely sure, you can disconnect the sensor connector and check this voltage with a multimeter or scanner. Everything is fine? Then we connect the sensor back.
By the way, on old foreign cars, the reference voltage “floats away”, and as a result, the normal operation of the probe and the entire system is disrupted. Most often, the reference voltage with the sensor turned off is higher than the required 0.45 V. The problem is solved by selecting and installing a resistor that pulls the voltage to the “ground”, thereby returning the reference voltage to the required level.
Further, the scheme of the sensor is simple. If there is a lot of oxygen in the gases washing the sensor, then the voltage on it will drop below the reference 0.45 V, to about 0.1V. If there is little oxygen, the voltage will become higher, about 0.8-0.9 V. The beauty of the zirconium sensor is that it “jumps” from low to high voltage at such an oxygen content in the exhaust gases that corresponds to a stoichiometric mixture. This remarkable property is used to maintain the composition of the mixture at the stoichiometric level.
Oxygen Sensor Test Method
Having understood how the oxygen sensor works, it is easy to understand the method of testing it.
Suppose the ECU gives an error related to this sensor. For example, P0131 "Oxygen sensor 1 low signal". You need to understand that the sensor displays the state of the system, and if the mixture is really poor, then it will reflect this. And replacing it is absolutely pointless.
How do we figure out if the problem is in the sensor or in the system? Very simple. Let's simulate this or that situation.
- For example, if there is a complaint about a lean mixture and low voltage at the signal output of the sensor, we will increase the fuel supply by pinching the return drain hose. Or, in his absence, by spraying gasoline from a syringe into the intake manifold. How did the sensor react? Did it show an enriched mixture? If yes, then there is no point in changing it, you need to look for the reason why the system supplies insufficient fuel.
- If the mixture is rich, and the probe displays this, try creating artificial suction by removing some kind of vacuum hose. Has the sensor voltage dropped? So he is absolutely correct.
- The third option (quite rare, but taking place). We create a suction, we squeeze the “return” - and the signal on the sensor does not change, it hangs at the level of 0.45 V, or it changes, but very slowly and within small limits. That's it, the sensor is dead. For it must be sensitive to changes in the composition of the mixture, quickly changing the voltage at the signal output.
For a deeper understanding, I will add that with a little experience it is easy to establish the degree of deterioration of the sensor. This is done according to the steepness of the fronts of the transition from a rich mixture to a poor one and vice versa. A good, serviceable sensor responds quickly, the transition is almost vertical (look, of course, with a motor tester). A poisoned or simply worn sensor reacts slowly, the transition fronts are flat. This sensor needs to be replaced.
Understanding that the sensor responds to oxygen, one more common point can be easily understood. In the event of a misfire, when a mixture of atmospheric air and gasoline is ejected from the cylinder into the exhaust tract, the lambda probe will respond to a large amount of oxygen contained in this mixture. Therefore, it is very possible for a misfiring error to occur indicating a lean air/fuel mixture.
I would like to draw attention to one more important point: a possible suction of atmospheric air into the exhaust tract in front of the lambda probe.
We mentioned that the sensor responds to oxygen. What will happen if there is a fistula in the release before it? The sensor will respond to a high oxygen content, which is equivalent to a lean mixture.
Please note: equivalent
In this case, the mixture can (and will) be rich, and the probe signal is mistakenly perceived by the system as the presence of a lean mixture. And the ECU will enrich it! As a result, we have a paradoxical situation: the error is “lean mixture”, and the gas analyzer shows that it is rich. By the way, the gas analyzer in this case is a very good assistant to the diagnostician.
How to use the information extracted with its help is described in the article "Gas analysis and diagnostics".
Oxygen Sensor: Conclusions
- It is necessary to clearly distinguish between an ECM malfunction and a lambda probe malfunction.
- You can check the probe by monitoring the voltage at its signal output with a scanner or by connecting a motortester to the signal output.
- By artificially simulating a lean or, conversely, enriched mixture and monitoring the reaction of the probe, one can draw a reliable conclusion about its serviceability.
- By the steepness of the voltage transition from the “rich” state to the “poor” state and vice versa, it is easy to conclude about the state of the lambda probe and its residual resource.
- The presence of an error indicating a defect in the lambda probe is by no means a reason to replace it.
Foreign cars produced since the 80s, in European or American models, already had a lambda probe in their design. It is involved in the fuel mixture formation chain. The sensor contributes to the balance of its formation. A good driver should know the signs of a malfunction of the lambda probe, since the performance of the passenger car depends on its condition.
How does the sensor work
The basic task performed by the λ-probe is to control the volume fraction of oxygen in each portion of the exhaust gases. The optimal value should be within the range of 0.15–0.3%. A significant deviation from the norm set by the manufacturer leads to negative consequences with the power plant of the vehicle.
Traditionally, the installation of the oxygen sensor is carried out in the exhaust manifold near the connecting pipes. Less often, in some models, its designers put it in a different place. In this case, the position does not affect performance.
There are variations of oxygen sensors with both a broadband type and a two-channel type. In the first case, a device is described from cars of high and middle class, and in the second case, from cars of the economy series and vehicles manufactured 2–3 decades ago. Also a characteristic feature of progressive designs is the balancing of correct readings and a high degree of accuracy.
It is important to know that due to the diligent work of oxygen sensors in cars, the engine life is significantly increased, the speed is balanced and fuel consumption is reduced.
Due to their design features and a certain location in the collector, a homogeneous signal is not expected from the sensor. This is influenced by the fact that the controlled exhaust gas is monitored after a large number of operating cycles. In fact, the λ-probe manages to respond after the fact to failures and send information about this to the computer.
Symptoms of an Oxygen Sensor Failure
Device malfunctions affect the operation of the motor as a whole. Failure can unbalance the well-coordinated functioning of the fuel system, which sends a mixture calculated in proportion to the combustion chamber.
The following symptoms appear:
- external air and exhausts penetrate inside;
- the case is depressurized;
- the device is obsolete;
- the oxygen sensor overheats due to improper ignition;
- there are problems with the wiring, which affects the quality of sending a signal to the electronic control unit;
- there were mechanical damage due to improper operation of the vehicle.
Usually, external consequences begin to appear gradually, so motorists do not always correlate the troubles of the ignition system with the lambda probe. Although it is not difficult to detect it and control the condition.
At first, fluctuations in performance occur in a wide range. Periodically worsening the quality of the fuel mixture.
Drivers should know how the car behaves if the lambda probe does not work. There are unreasonable jerks in work, uncharacteristic pops from the side of the engine or closer to the exhaust. Often, a characteristic indicator light is on on the dashboard while driving. Such anomalies should not be ignored, but it is worth conducting a primary diagnosis.
It is important to check the sensor with a significant decrease in power. Moreover, this is carried out for cases where there are no obvious reasons for this. You will need to look into the knot when the car stops reacting briskly to pressing the gas pedal, and at the same time pops are heard from the engine compartment. Noticeable overheating of the motor should not be overlooked.
Manufacturers of modern cars can lay the start of signals on the dashboard, as well as a complete blocking of the movement of the car. The driver will only have to call an emergency evacuation.
The most problematic failure option is the loss of tightness of the sensor. We do not recommend continuing to drive in this case, as it can lead to more serious engine damage. With such a defect, the gases from the exhaust are not sent into the pipe, but are able to penetrate into the area where the reference atmospheric air is located. Thus, the sensor detects an excess of molecules and sends incorrect signals to the ECU, disabling it.
Loss of power - a true sign of a decrease in the tightness of the lambda probe. Also, the engine starts to tap and there is a smell of exhaust in the cabin. You can notice the symptoms by an increase in soot on the exhaust valves and near the candles.
The device will have to be tested or completely changed. In a service station, expensive oscilloscopes are used, and in a home garage, multimeters are used for this. Based on the results of the check, the final decision is made on what to do with the sensor.
As a rule, most motorists do not carry out repairs with oxygen sensors. They simply change or mount a special homemade plug. It is preferable to carry out final diagnostics on high-quality equipment to make sure that it is the lambda probe that is to be repaired.
The oxygen sensor, the symptoms of which are known to most experienced car owners, plays a significant role in the functioning of the car. For all its invisibility and small size, this regulator adjusts the fuel mixture, thereby helping the power plant.
A car engine that receives a well-mixed air-fuel mixture runs at maximum efficiency. Unfortunately, the sensor regulator or lambda probe, as it is also called, tends to deteriorate.
Causes of disruption and obvious signs
As a rule, the following reasons lead to a violation of the functioning of the sensor:
- Some kind of aggressive liquid, such as antifreeze or brake fluid, gets on the sensor.
- Problems can begin if the owner used chemically active agents in the process of cleaning the regulator housing.
- If the fuel for the car contains a large amount of lead compounds.
- In the event of a significant overheating of the regulator, which occurs either due to the use of poor quality fuel or due to filter clogging.
Regulator malfunctions can be judged by obvious signs of an external nature. It's easy to notice. It is enough to pay attention to the following points:
- Fuel consumption has increased sharply.
- The car jerks jerkily, even when the engine is warm.
- The color and smell of exhaust gases has changed.
- Catalyst malfunction.
Of course, the general operating conditions also have a negative effect on the sensor. The electrical wiring or the regulator itself may be damaged if the standard vehicle operating rules are not followed carefully.
steps
In turn, experts see two main stages in the deterioration of the sensor.
At the first stage of a sensor malfunction, there is an increase in the reaction time of the engine to pressing the gas pedal. The power unit reacts sluggishly, when you press the accelerator, the “check” starts flashing, the pedal goes down - the flashing stops. At this stage of the malfunction, the driver notices a deterioration in traction, acceleration dynamics and an increase in fuel consumption (slightly so far). As a rule, this stage of a regulator malfunction can last about a year.
The second stage is already much sadder. Most car owners at this stage are thinking about why this oxygen sensor is actually needed. Normal acceleration completely disappears, the car “dulls” even on a completely flat road. Another distinguishing feature of the second stage can be called a decrease in the speed of the power unit, even when the accelerator is pressed into the floor. Pops may be heard in the intake manifold.
For complete certainty, it is recommended to start the car "cold". If the oxygen sensor is faulty on the second severity scale, the car will only run perfectly for the first few minutes. When the device starts to function by sending signals to the ECU, problems will immediately arise.
Regulator check
If there is a suspicion of a malfunction of the regulator, it is recommended to start with an assessment of its external condition. In most cases, if the sensor is faulty, it becomes covered in a layer of dirt or soot. The normal appearance of the sensor, as a rule, indicates its normal operation, but it is worth continuing to check.
- The regulator should be disconnected from the block.
- Then connect it to a voltmeter that has a fairly high accuracy class.
Note. The connection diagram of the regulator to the voltmeter should be based on its pinout: the black wire of the sensor is responsible for the signal (goes to the controller), the white wires are responsible for heating, the gray wire is for grounding.
Checking the voltmeter readings is a diagnostic on the dynamics of the car's power plant. For example, if cruise mode (2500 rpm) is engaged, with the vacuum tube removed, a normally working regulator should output 0.9 V (a little more or less). If the sensor readings are below 0.3 V, then the device is definitely faulty.
Checking the sensor may have another mode. It is possible to simulate forced air suction, thereby depleting the air-fuel mixture. In this case, the regulator readings should be less than 0.2 V.
Another test mode is associated with the intermediate position of the motor. In other words, if the speed of the power plant is within 1500 rpm, the regulator should show a value of 0.5 V.
In case of complete evidence of a sensor malfunction, it should be dismantled and replaced. And here it is necessary to adhere to certain rules.
- It is better to change the regulator on a used car, so to speak, “hot”. This gives more chances not to break the thread.
- It is also recommended to slightly raise the connector of the new regulator, thereby protecting the device from dirt and moisture.
- And finally, experts advise treating the sensor housing with “graphite”, even with factory lubrication.
Almost all modern cars have an oxygen sensor. The device may be located in different ways. On some vehicles it is near the catalytic converter, on others it is in the exhaust manifold. 
What to do if a faulty sensor is caught on the road
If a sensor malfunction caught on the road or you need to go somewhere urgently, but problems with the probe have not been resolved, what can be done? The solution is ingenious to simplicity - you just need to turn off the probe. Of course, the flashing of the “check” will not disappear anywhere until the engine stops, and the dynamics, in principle, will not be normal. But you can easily get to the car service, albeit without amenities.
You need to install a probe that is recommended by a specific automaker. By putting some kind of "left" device, albeit for the sake of economy, you can subject the engine to unbearable loads and problems. Undoubtedly, engine repairs will cost a lot more than buying a quality oxygen sensor.
Regulator replacement
Replacing the oxygen sensor on domestic cars, as a rule, does not cause any particular difficulties. The only difficulty may lie in the boiling of the probe, after which it is practically not amenable to mechanical action. But even for such cases, there is an effective and step-by-step instruction. It is shown below.
- The car rises to the overpass.
- The protection of the power unit is removed.
- The hood opens, work begins with the wires of the probe. The wiring from the oxygen sensor can be found on the CO (cooling system) hoses. They are fixed with clamps.
- The plastic clamp holding the wiring is cut;
- The sensor is unscrewed with a key to "22".
If the device is not removed, the sensor is boiling. We act according to the following scheme. We spray the regulator with WD-40, wait a bit and try to remove it again. If it doesn’t work again, start the engine and heat up the exhaust system a little, pour water on the regulator and try again. If it does not help, you will have to heat the sensor directly with a soldering iron, tap it with a hammer (not hard) and unscrew it.
Install the regulator in the reverse order of removal. You must not forget to connect the connector and fix the wiring to the hoses.
Knowing the signs of a malfunction of the lambda probe, you can react to it in time and replace it. A normally functioning sensor is a high-quality and trouble-free operation of the engine. This motorist should never forget.
The exhaust system of vehicles has changed significantly over the past few years, several additional elements have appeared in its design that allow vehicles to be operated without violating international environmental standards.
For example, one of these elements is an oxygen sensor, the signs of a malfunction of which should be known to every car owner. We will consider in detail the purpose, design features and common malfunctions of the lambda probe in the framework of this publication.
What is an oxygen concentration sensor for?
In practice, many owners of automotive equipment are not even aware of the existence of this element. Its purpose is to determine the concentration of oxygen in the exhaust gases and the subsequent transmission of this information to the computer. Based on this, according to the algorithms embedded in the system memory, the fuel-air mixture is corrected for its complete combustion in the cylinders of the power unit.
The location of the oxygen sensor is the exhaust manifold. On most models, the lambda is mounted directly in the area of the catalytic converter. Regardless of where the sensor is installed, the correctness of its readings and system performance will not be affected. There are two types of lambda probe:
- Broadband
- dual channel
Note that the second type is included in the design of old vehicle models that were produced before the 90s. All modern models have a broadband lambda, which captures all deviations with high accuracy to ensure the most correct mixture formation. At the same time, a properly functioning sensor of such a system can really reduce fuel consumption and ensure optimal crankshaft speed of the power unit.
Causes of malfunction of the lambda probe
Sensor failure symptoms can vary. Initially, its malfunction is reflected in the quality of the fuel mixture. For example, its incorrect operation can be triggered by the presence of various deposits. And the most common cause of lambda failure is a violation of its tightness caused by natural wear and tear of the material of its manufacture. Mechanical damage to the oxygen concentration sensor is less common because the element is well protected.
Also, the sensor may work intermittently, or not function at all due to a power failure. The contact groups of the lambda probe undergo oxidation, as a result of which the device starts to work incorrectly, transmitting incorrect readings to the computer. This leads to disruption of the mixing process.
Incorrect ignition timing is one of the possible causes of an oxygen sensor failure. Often a similar problem occurs on vehicles in the ignition system of which a distributor is provided. In addition, damage to the wiring and problems with spark plugs also leave their mark on the functioning of the lambda probe. This can be recognized by the friction of the engine and its incorrect operation when the crankshaft speed is increased.
Detailed definition of the problem
Among the common signs of a malfunction of the lambda probe are the following:
- increase in fuel consumption;
- the occurrence of jerks while driving;
- a sharp decrease in the power of the power unit;
- unstable idling;
- the appearance of a sharp, toxic smell in the exhaust gases of a car.
It must be emphasized that the symptoms listed above are not always the result of a malfunction of the oxygen concentration sensor. If these symptoms are found, a thorough check of the lambda probe must be performed. Let's consider this process in detail.
Methods for diagnosing a lambda probe
You can test the sensor in one of the following ways:
- During the visual inspection
- Checking with a multimeter
Let's start with the first method. First you need to disconnect the connector from the sensor and inspect the condition of the contacts, the integrity of the wires should not be broken, and all connections should be tightly held. After that, we examine the sensor itself. It should not have any deposits and violations of the integrity of the structure.
Soot deposits can be cleaned, its formation is caused by the combustion of an overly enriched fuel mixture, as a result of which lambda patency is impaired. This leads to the fact that the device starts to function incorrectly. The most detrimental to the sensor are lead deposits, which have a silvery-shiny color and are caused by the use of low-quality fuel and engine oil. There is no way to get rid of them, a complete replacement of the device is recommended.
The process of checking the lambda probe with a multimeter is not particularly difficult. To implement it, it is necessary to connect the signal wires of the sensor to the tester probes, then start the power unit and keep its speed at 2.5 thousand. Next, we drop the accelerator, pull out the suction and look at the multimeter scale.
The complete failure of the oxygen concentration sensor is indicated by the absence of voltage, or its low value (less than 0.8V). Since the design features do not allow the lambda probe to be fully restored to working capacity, a complete replacement of the expired element will be required.
How to replace yourself?
As you can see, in most cases of failure of the lambda probe, its repair makes no sense, so the best solution to the problem would be to replace the faulty element, especially since this process is not difficult.
Before replacing, it is necessary to de-energize the vehicle's on-board network, and then remove the block from the sensor (on some models it can be additionally secured with clamps). Since the lambda is included in the design of the exhaust system, accordingly, the element is constantly working under high loads. It is not always possible to unscrew it the first time. This should be done carefully so as not to damage the threads in the exhaust manifold pipe.
After the failed element is removed from its seat, we clean the threads from dirt, install a new lambda probe and screw it in, trying not to overtighten it.
The importance of the oxygen concentration sensor in the exhaust system of a car cannot be underestimated, since its failure will provoke incorrect operation of the power unit, which is extremely detrimental to its elements. For this reason, you need to learn how to identify its breakdowns in time and correctly.
This article will talk about what a lambda probe is, we will also consider the symptoms of a malfunction of this node. It is also called an oxygen sensor. It is installed in the exhaust tract of an automobile internal combustion engine. Moreover, this sensor is placed on both gasoline and diesel engines.
Basic information about the oxygen sensor
The lambda probe is similar in principle to its operation as consisting of a solid ceramic electrolyte based on zirconium. Doping of ceramics with yttrium oxide was also performed. From above there is a sputtering with a thin layer. It turns out that one electrode perceives the exhaust gas, while the other receives air from the atmosphere. It is due to this that the parameters of the working gas are compared with normal atmospheric air. It is also worth noting that the most effective work is carried out at temperatures above 300 degrees. It is with this heating that the zirconium electrolyte begins to conduct current. And now it's time to learn about what affects how the lambda probe works. Signs of malfunction "Priora", for example, will allow you to identify even by ear.
The principle of operation of the lambda probe
Due to the fact that there is a difference in the mass content of oxygen, an output voltage appears on the sensor electrodes. To increase the sensitivity of the device at low temperatures, for example during engine start, forced heating must be used. The electrical coil is located in the ceramic body of the lambda probe. It has a connection to the vehicle's on-board network. There is also an element of the oxygen sensor, which is based on It changes its resistance when the engine is running. It is on this principle that the lambda probe works. The symptoms of a VW Golf 3 malfunction are the same as in domestic cars.
Operation of the oxygen sensor
At the moment when the engine starts and warms up, the engine operates without data coming from the lambda probe. All correction of the air-fuel mixture occurs according to data received from other devices. In particular, these are dampers in the throttle, engine temperature, crankshaft speed. The main feature of the lambda probe based on zirconium is that with a slight deviation from the norm of the oxygen content, when analyzing the composition of the fuel mixture, a significant change in the output voltage occurs in the range of 0.1-0.9 Volts.
Titanium oxygen sensors
There are also sensors made of titanium dioxide. Then, when there is a change in the mass fraction of oxygen in the exhaust gases, they gradually change the volume resistance. Voltage generation does not occur with sensors of this design. They are much more complex than zirconium, they are used on very expensive cars, such as BMW, Nissan, Jaguar. As a rule, titanium-based devices are not used on budget cars, as they are more expensive. On cars of the middle and low class, a cheaper zirconium lambda probe is used. Renault-Megan 2 shows signs of malfunction that are no different from those present on domestic cars.
Differences in lambda probes
It is worth noting that the principles of operation for oxygen sensors are the same, regardless of who the manufacturer is. The only difference is the dimensions of the body of these elements. There may also be a slightly different connection, often there is a difference in the connector. All sensors, as mentioned above, are heated or not. Therefore, they differ in the number of wires to connect. According to the materials, the differences are as follows: either zirconium or titanium. In the latter, the heater output is always red. There are also types for diesel engines. They are more broadband. It is impossible to install such a lambda probe on a gasoline engine. Symptoms of a malfunction ("Skoda-Octavia" are also of interest to many motorists) are accompanied by the output of an error code with a brief description.
Why does the lambda probe fail
Very often, the cause of premature failure is the poor quality of gasoline. Iron and lead, which can be present in bad gasoline, instantly clog platinum electrodes. Consequently, the oxygen sensor fails, it cannot normally take all the readings. If they have a strong production, then a certain amount of oil will fall into. This is also the cause of premature failure of the oxygen sensor. Even if a little solvent or detergent accidentally gets on the oxygen sensor, you can immediately say that it is broken. He does not survive the ingress of such solutions. The destruction of the lambda probe occurs when pops occur in the exhaust system. Ceramic is very brittle, so such sharp blows can break it. If the ignition angle is set incorrectly or if the air-fuel mixture is excessively enriched, the sensor housing will become very hot. This causes premature failure.
Less common causes of failure
Please note that when installing a lambda probe, you cannot use various sealants that are based on silicone. It is also possible to destroy the lambda probe if you try to start the engine many times, making small pauses between attempts. As long as the engine doesn't start. This will inevitably lead to the fact that the air-fuel mixture will accumulate in the exhaust system. After some time, it will ignite and create a powerful blast wave. Even a poor-quality contact, either in the output circuit, can destroy the device. The total resource of the elements ranges from 30..70 thousand kilometers. It largely depends on the conditions under which the operation takes place. Sensors with additional heating have the longest service life. Most foreign cars use this design lambda probe. The symptoms of a malfunction, ("Ford Focus 2" or "Skoda" are in your possession) are the same. Therefore, you can diagnose yourself if you correctly recognize all the symptoms.
Frequent sensor failures
Among the most popular breakdowns, one can note a non-working heating element, as well as loss of sensitivity. As a result, the performance of the device decreases. Most importantly, try not to replace the lambda probe with any imitators. The electronic control unit will not be able to recognize someone else's signal. Therefore, the correction of the fuel mixture according to this simulator will not occur. Please note that if the oxygen sensor has successfully worked in the conditions of our country (poor-quality gasoline), and its service life has clearly been more than three years, then you can not even contact the diagnostician. Immediately it is necessary to replace the lambda probe. Signs of a malfunction "Skoda" shows clearly with a run of over 70 thousand km. Some models of oxygen sensors may even have a resource of just over 30 thousand kilometers.
How to determine if the sensor is faulty
If there is unstable operation of the engine at low speeds, it feels as if the engine is “troiting”. And at the same time, the consumption of gasoline increases, the dynamics of the car worsens. You will often hear crackling sounds coming from the catalytic converter after you turn off the engine. It is also possible to increase the (significant) temperature of the catalyst itself. Sometimes it is so heated that the metal simply heats up. In some vehicles, a malfunction can also be judged by the Check Engine warning light. Only, unfortunately, not all electronic control systems allow you to identify and indicate the malfunction of this element.
