Removing the catalyst is a topic that worries many car owners, often instead of catalytic converters, car owners install flame arresters, stingers ("spiders"), this solution allows you to avoid buying expensive parts, spend less time repairing the exhaust system. But on cars with two oxygen sensors, the physical exclusion of the catalytic element does not give the desired results, and in order to get rid of errors in the engine management system, it is often used electronic snag lambda probe.

In this article we will look at how you can trick the control unit, which methods are most effective. It should be noted right away that not all methods are suitable for a specific car model; each car must be approached individually.

Mechanical snag lambda probe

Any automobile catalyst is a muffler can with a metal or ceramic honeycomb, coated with a precious metal (gold, platinum, etc.). Due to the oxidation reaction, exhaust gases passing through such a device are cleaned of harmful impurities, and the level of exhaust toxicity is reduced.

The catalytic converter (KN) operates under conditions high temperatures, therefore, its resource is relatively small. The service life of the part is further reduced when using low-quality fuel - the honeycombs are clogged with carbon deposits resulting from incomplete combustion of the fuel mixture. Buying a new KN is quite expensive, and since it has to be changed quite often, many car owners are trying to get rid of this element of the exhaust system by installing a flame arrester or stinger.

Simple removal of KN has a side effect: on cars with engines Euro-4 and higher, an oxygen sensor installed behind the catalyst records an excess of the exhaust toxicity norm, as a result, a lamp on the instrument panel lights up Check Engine... There are three ways to get rid of the error:

• install an additional mechanical spacer;
• make changes to the electrical circuit oxygen sensor;
• reprogram the engine control unit.

Mechanical snag is a metal sleeve of a certain length, with a small diameter hole inside. Also in the interior of this fixture is catalytic coated ceramic chips. In fact, the sleeve is a mini-catalyst, but here only the exhaust gases that enter the oxygen sensor are cleaned. It should be noted that there are also simple blendes made in the form of an ordinary sleeve with a hole, inside of which there are no elements. Any turner can make an elementary spacer, in this case it is not necessary to buy a factory product. The advantages of such devices:

• inexpensive price (on average from 400 to 1000 rubles);
• ease of installation;
• reliable and simple design.

However, the mechanical trick has its drawbacks - on some car models it is not possible to install the device (there is not enough space due to design features), the device does not always give the desired effect (the error does not completely disappear). It should also be noted that on cars with Euro-5 engines electronic system with the help of an additional spacer, it is impossible to deceive, the Check Engine still continues to light up here.

DIY electronic "fraudulent" scheme

The electronic snag of the oxygen sensor is a circuit included in the ECM electrical circuit. By installing additional components, the signal supplied to the control unit is corrected, and the ECU receives such data from the sensor, as if a catalyst was installed on the car, and there are no changes in the exhaust system.

Usually, four-contact lambda probes with an electric heater are modernized with their own hands, a heating element is needed to warm up the oxygen sensor on a cold engine - the whole point is that the catalyst turns on only after heating exhaust system not lower than 360 degrees Celsius. The heating of the oxygen sensor is powered by the ECU (control unit), while the polarity of the wire connection does not matter (usually white wires are connected to the heater).

In electronic snag, the electric heater is not subject to modernization, all changes concern only the signal contact. In the simplest circuit, there are two main components - a high-resistance resistor and a capacitor with a capacity of about 1 Microfarad, and it usually looks like this:

• the resistor is included in the break of the signal wire;
• a capacitor is installed between the mass connector and the signal.

The capacitance of the capacitor and the resistance of the resistor can be different, their value depends to a large extent on the car model and the type of engine installed.

How to make electronic snag on an Opel Zafira car

The fraudulent scheme on the Opel Zafira car is compiled according to the same principle as described above; to install the blende, a non-polar capacitor of 1 MkF and a resistance of 1 mOhm 0.5 W are required. We carry out work on the installation of a simple device in the following order:

All ECU errors must be reset before starting the test. It should be noted that installing a snag does not always give positive results, in some cases the error may appear again. The most reliable way is to reprogram the control unit, but here it is important to find the correct firmware version.

Oxygen sensor emulator

The lambda probe simulator is effectively used on cars with a remote catalyst or on cars with gas equipment installed, the device is connected to electrical diagram engine management, quite reliably emulates the operation of a real lambda probe. Ready-made factory emulators can be found in retail, the basis of the simulator circuit is an electronic timer, in the role of which the popular NE555 microcircuit is most often used.

Basically, industrial emulators are installed after switching the car to gas - after installing gas equipment (LPG), the composition of the fuel mixture changes, therefore the lambda probe detects an increased content of toxic substances in the exhaust gases, an error appears. Let's consider how to install the Zond-4 model oxygen sensor simulator on a car with LPG.

Probe-4 is equipped with a three-color LED indicator that signals the state of the fuel mixture (lean or rich). When the indicator lights up, it means:

• green - poor mixture;
• yellow glow - fuel / air ratio is normal;
• red indication - the mixture is re-enriched.

The emulator is attached to engine compartment, connects to the car's electrical circuit using four wires. Using Zond-4 is very simple, we connect the wires as follows:

After connecting, check the operation of the Probe-4: the indicator should not light up on petrol, while on gas it should glow green, yellow or red.

Scheme of cheating a lambda probe with a diode

You can deceive the second oxygen sensor on a car in another way, only in this circuit, instead of a resistor, you need to install a diode, for example, brand 1N4148. Deception is done here as follows (for example, a Mazda 323 car with gasoline engine 2.0 L):

• cut the signal wiring (on Mazda it is black);
• the anode of the diode is connected to the lambda probe;
• the other output of the signal going to the control unit is connected to the cathode;
• we also connect one of the leads of a non-polar capacitor with a capacity of 4.7 MkF to the cathode;
• the second capacitor tap is connected to the mains wire (on Mazda it is gray), of course, we solder all the wires.

Such a scheme allows you to effectively get rid of errors in the oxygen sensor circuit, but you need to keep in mind that the lambda probe itself must be serviceable.

Oxygen sensor quick test

Many car owners have repeatedly confirmed that the electronic snag works normally only if the lambda probes on the car are working properly. It is quite simple to quickly check the performance of the sensors; you only need a multimeter for diagnostics. We check in the following order:

But it is worth noting that such a check does not give an idea of \u200b\u200bone hundred percent serviceability of the sensor, it only confirms that the lambda probe is in working order.

Catalytic converter lambda probe emulators 2 (EURO-3 standard and higher)

Due to the fact that the cost of a new catalytic converter (especially the original one) is often equal to half the cost of a new engine, so inquisitive minds of motorists began to research and experiment on this topic ...

The life of such an expensive component of a modern car depends largely on the quality of the fuel used, (which is still a problem), its brand (it is enough to refuel once, for example, with leaded 80 and the neutralizer will become unusable) and many other factors ... but this is a topic for a separate article we will not go deep into it !!!

In a situation when the catalytic converter is clogged and, accordingly, does not pass normally exhaust gases, it must be urgently changed, since the engine may be damaged (which leads to its expensive repair) and not only !!!

Another situation is when the converter is still able to pass normally exhaust gases, but is no longer able to perform its function of cleaning the exhaust from polluting CO and CH (this is most typical for old-age or mileage cars), the engine ECU goes into emergency mode, i.e. n. "hobble to the garage." Accordingly, there is no train ride on such a car for a long time and comfortably, fuel consumption increases, power characteristics deteriorate, poor throttle response, etc. ...

The only way out of the above situations is 2:

• The most correct and environmentally friendly replacement for a new original catalytic converter, or, as an option, disassembly with replacement of the old element with a new one (now they are sold separately for some machines), which will require a simple "grinder" and a welding machine (you can find many videos on this on the Internet type of repair)
• Another not entirely correct and not environmentally friendly way out of this situation is the emulation of the catalytic converter. There are many options here, this is a replacement for a flame arrester of a suitable size and fastening, an analysis of the old catalyst with the removal of the element and filling, for example, with a mesh, followed by brewing, etc. ...

When we go along the path of emulation of KN (catalytic converter), we get some benefit, the power indicators of the engine are improved, a cheap converter, everything seems to be simple, cool, but no !!! The engine ECU, analyzing the indicators of both lambda probes of the manager and the controller, does not see the difference between them and switches the engine into emergency mode. A simple removal of 2 lambda probes also cannot solve the problem again in emergency mode !!! As an option, flashing the ECU with software removal of 2 lambdas, but there are difficulties along the way:

• lack of good specialists with the same equipment
• possible irreparable damage to an expensive ECU
• lack of good, reliable software
• there is no guarantee normal work engine after flashing (in factories, too, specialists sit !!!)

But we will go in other ways - electronic and mechanical emulation of the normal operation of the 2 lambda probe. There are many schemes described on the Internet, from simple to complex, but I am alex.ho.ua from personal experience settled on one and its variations on the example of 2 lz from a Subaru car:

According to this scheme, a serviceable 2lz remains in the SC in its place in the break of the signal wire, a constant low-power resistor of 1 megohm is soldered and shunt the signal and ground wire of the ECU with a constant capacitor for 1 microfarad with an operating voltage of 16 volts and above.

An approximate oscillogram of the operation of this circuit (emulation yellow curve, blue without emulation) is below:

* Note auto.18 in if the circuit worked without switching on emergency mode then we do not change anything in it, if not, then we solder a variable resistor 1-1MΩ, connect an oscillograph to the signal wire at the output of this emulator (from the computer side) and look at the shape and amplitude of the signal. Perhaps you will also have to experimentally select a shunt capacitor from 0.1-10Mkf

And one more circuit of the lambda probe emulator ...

A simple emulator with adjustment of the "air-fuel ratio" can
build on 555 multivibrator module
The infra-low frequency is provided by the large value of the capacitance of the capacitor C2. The switching frequency is controlled by the resistor R1; in its middle position
frequency approx
equal to 0.5 Hz. The emulator signals are shown in Fig.
"Mix quality" is regulated by resistor R6. IN
middle position
"stoichiometric mixture"
0.110.9 V (oscillogram No. 1). In the right (according to the scheme)
position of the slider of the resistor R6 " rich mixture"
0.5550.9 V (oscillogram No. 2). In the left (according to the scheme)
position of the slider of the resistor R6 "lean mixture" 00
0.45 V (oscillogram No. 3), which is determined by the forward voltage of the diodes
VD1, VD2. Preferred
diodes of the KD925V type. In intermediate positions
varying degrees of "enrichment" or "impoverishment".
The details are as follows: bipolar transistors BC547C or BC847C, diodes 1N4007, LEDs
any with a diameter of 3 mm, electrolytic capacitors with a voltage of 25 V.

Catalytic converter lambda probe emulator 2 (EURO-3 standard and higher) version 2

This circuit can be considered not only as an emulator of 2 DCs but also as a temporary replacement for a faulty 2 DCs !!!

To emulate the DK2 signal from the DK1 signal, the following scheme was used (by changing the resistance of the trimming resistor and the capacitance of the capacitor, we adjust the signal to the value required for normal regular work ICE ECU):

A 300Ω / 2W resistor is used to emulate the DK2 heater. Can be replaced with a coil winding from a conventional 12V car relay. Alternatively, you can use a heater (provided that it is repaired) 2 DK.

Check is off, dynamic characteristics have not changed.

The original connectors (DK1, and input to the ECU DK1 and DK2) have been replaced with "Volgov" 4-pin connectors. The whole device is mounted on a circuit board, connections are simply wire.
Upd. Completely chewed up scheme:

Note * To set up this circuit, it is advisable to use an oscilloscope observing the curve of the emulated signal of the 2 lambda probe.

Catalytic spacer for lambda probe (mini catalyst)

I must say right away that these spacers are not tubes with a hole and a mesh, as many people think, including those who are trying to fake them. That is why you do not have to "modify the hole with a drill" so that the annoying CheckEngine light would finally go out, as sellers of similar products can advise you.

Our spacers have an efficient catalytic element capable of operating at low temperatures, due to which the composition is provided on the sensor exhaust gasesequivalent to the composition passed through the standard catalyst, the same amount of oxygen.

Why is this needed? Believe me, not only so that the light goes out, but above all, so that the engine management system works correctly. Indeed, using the catalytic converter probe, the engine control unit monitors the integral ratio of the mixture and gradually adjusts the mixture, ensuring the speed and efficiency of regulating the mixture using the catalytic converter probes. Almost every good diagnostician knows that the recovery time is much longer than the response time for the mixture control circuit using the primary probes in case of a deviation from the specified mixture. This is what determines the need for the correct operation of the catalyst probes. The slightest deviation of the long-term correction of the fuel supply, formed from the readings of the catalyst probes, causes a state when the correction by the forward probes will be in the recovery zone most of the time, i.e. overshoot will constantly occur and the fuel supply will not form correctly. And this is fuel consumption and power ...

What do you need, a properly working machine or dubious savings in the case of buying cheap fakes? It's up to you to decide ...

Moreover, the test results of our spacers showed that the wrong work catalyst adaptations return to normal. It should also be noted that the resource of the built-in catalyst is much higher than that of the standard catalyst, but only if the mixture formation system is working properly and correctly.

Of the shortcomings, only one can be noted - the standard probe rises by 32mm and sometimes it is problematic to install a probe with a spacer. There is nothing you can do about it - you have to weld the nut in another place.

But you can make the spacer yourself ...

In a nutshell - the essence of the method lies in the fact that it is necessary to make the lambda probe "breathe" "a little further" from the exhaust tract, yes "through a small hole" - as a result, we will also get a weaker sinusoid and the brain will think that everything this is the "fault" of a normally working catalyst.

Here is a photo of the spacer (I will make a reservation right away - the spacer is slightly incorrectly made on the photo - "this hole" should be 1-2mm in diameter, although there are cases when even with a hole in 6mm Check does not light up anymore, but you should start with a hole in 1- 2mm in diameter (as indicated in the drawing below - 2mm).

And here is the drawing that we print on the printer and calmly go with it to the turner:

To be continued...

Paid, everything is fine, started saving and then ... Check Engine lights up! An indicator that all motorists are afraid of, and which, as a rule, does not bode well ... You come to the installers, and they tell you that the lambda probe (oxygen) sensor gives an error because fuel mixture when running on gas, it has a different composition than on gasoline.

And what's next, most car owners ask? How to deal with this? And here you are told several options for getting out of the situation, among which there will certainly be the installation of a lambda probe emulator. Here more and more questions arise, continuous confusion is shorter, you have the feeling that they are trying to cheat you or they are being promoted again for money ... So in order for you to understand what this is about and what is a lambda probe emulator and what it is for , we decided to write this article... Sit back, now we will tell you everything in order in simple and understandable words for you ...

To begin with, I'll tell you "where the legs grow from" and why such a problem arises, that is, why the "Check" lights up.

How does a lambda probe work

An oxygen sensor or oxygen sensor, as well as a lambda probe, is a sensor that monitors the toxicity of the exhaust. How does this happen? During the combustion of a fuel-air mixture (FA) consisting of oxygen and gasoline (diesel oil or gas), harmful elements are formed in the exhaust that pollute the atmosphere. So, in order to prevent pollution, smart people came up with the idea of \u200b\u200bmonitoring the toxicity of the exhaust using such sensors. Lambda monitors what percentage of oxygen is contained in the exhaust and sends data about this to the ECU (brains, in other words), which in turn concludes whether the mixture is "rich" or "lean" and then decides whether to increase the fuel supply or decrease it. The ideal air to fuel ratio is considered to be: 14.7: 1. This proportion is called stoichiometric, and is repelled from it when setting fuel equipment and all engine systems as a whole. In addition, it has been proven that it is this ratio that causes minimal harm to the environment. So, when the engine is in good working order and works on its familiar native fuel assembly, everything is fine and there is no "Check". But as soon as you install HBO, the composition of the mixture will change significantly, and the lambda, which "stands on guard and sees everything," will somehow notice it, report it to the "brains", which will notify you about this with the appropriate inscription on the panel. More details about why "Check" lights up on a car with HBO. So, we sort of figured it out, let's move on.

What is a lambda probe emulator, how does it work and what is it for?

A lambda probe emulator is a device that, roughly speaking, "substitutes for concepts", that is, it simulates or intercepts and corrects the signal coming from the lambda and sends it further in the correct correct form, that is, to the ECU. The lambda probe emulator is installed on injection cars in which oxygen sensors are present, either during or after the installation of HBO. Depending on the type and brand of the manufacturer, the emulator copies the signal of the lambda probe and thereby prevents errors during engine operation on the gas-air mixture.

Installing a lambda probe emulator

The emulator is installed in the engine compartment in places protected from moisture and high temperatures. At the same time, the emulator of the lambda probe should be located in a place where its operation (signal indicators) will be convenient to monitor, and also, if necessary, make adjustments to its operation.

Connecting an emulator

• The blue wire connects to the gas / petrol switch.
• The white wire connects to the injector ECU.
• The white-blue wire is connected to the lambda probe.
• The black wire is connected to ground.

Attention!!! An incorrectly connected emulator can lead to undesirable consequences, up to the complete failure of the standard ECU.

How it works?

When the engine switches to gas, which is signaled to the emulator by a signal from the gas / petrol switch, the control signal from the lambda probe is automatically disconnected from the engine ECU. Instead of a standard signal, the ECU receives emulation, that is, a signal from the lambda emulator. The signal coming from the lambda is transmitted to the emulator and displayed as control lamps, each of which means the following:

• Green - poor mixture;
• Yellow - normal proportion (intermediate state);
• Red is a "rich" mixture.

When the engine runs on a kind of fuel, that is, gasoline, the signal input and output are short-circuited, while the oxygen sensor signal can freely go through the lambda probe emulator and exit without any changes.

In general, something like this ... I hope now everything is clear to everyone, and the question of what is a lambda probe emulator can be considered closed !? Thank you for your attention and see you soon on the pages.

Quite a frequent occurrence for owners of cars with LPG installed is the "Check Engine" button that lights up, about what this inscription means and why this happens, we figured out in detail. Today, the topic of our article will be to consider a solution to one of the most common problems that can cause the inscription "Check Engine" - a failure of the lambda. The cheapest and most common solution to this problem is to install a lambda probe emulator. What is a lambda emulator and how does the "snag" help the owner of a car with LPG?

What is a lambda probe

To understand why to use a lambda blende (catalyst emulator), you must first understand the principle of operation of the probe itself. Often, modern car owners are not aware of the fact how “smart” (computerized) their cars have become. This process went gradually, from subsystem to subsystem - so, the lambda probe appeared in serial machines even in the last century. In fact, lambda is such a specialized sensor for measuring oxygen, which allows you to determine its residual amount in the exhaust of a car engine.

Based on the signal from this sensor, modern electronic vehicle control units (ECUs) decide how “lean” or “rich” (supersaturated with oxygen or fuel) the air-fuel mixture entering the ICE cylinders is. Factory configured with modern power units manufacturers are usually guided by the so-called "stoichiometric" ratio of air to fuel:

• for gasoline ~ 14.7: 1,
• for liquefied gas ~ 15.4-15.6: 1,
• for methane ~ 17.2: 1

This value ensures the most complete combustion and the minimum content of associated harmful gases in the exhaust.

When using LPG, the problem is that the car already runs on a different fuel, and for its most complete and efficient combustion, a different ratio of components (gas and air) in the fuel-air mixture is required.

Thus, when installing gas equipment, not only the fuel on which the car travels changes, but also the oxygen content in the exhaust.

Of course, most HBO installers do not bother with tuning the car's ECU, informing him about the installed HBO. After a few tens of kilometers, the lambda probe, responding to a change in the amount of oxygen in the exhaust, gives a signal about a malfunction, which does not know anything about the installed LPG electronic unit driving a car. And that, in turn, to the car owner, through the "Check Engine" indicator on the dashboard.

What is a lambda emulator for?

An emulator is a system or device designed to copy (or emulate) the functions of one system to another. Moreover emulated behavior should be as close as possible to the behavior of the original device.

Thus, electronic emulator the lambda probe intercepts and corrects the existing signal from the original oxygen sensor in such a way that the ECU injection engine did not give an error when the car was running on gas. Usually, a lambda probe emulator is installed on a car either immediately during the installation of LPG, or a little later, after an engine error is detected.

Emulators "good" and "bad"

It is important to understand that there are both simple emulators of lambda probe trickery and rather complex systems that adjust the readings of a standard oxygen sensor. The task of the first, most simple lambda tricks is to prevent the appearance of the inscription "Check Engine" on the indicator, and to create visibility good work systems. But more advanced representatives of lambda emulators are designed to intercept the signal of the original sensor, correct it, and transmit the already corrected signal to the standard ECU, thereby improving the operation of the entire car.

Of course, the lambda probe snag is made from some general considerations so that the engine operating modes are more or less close to optimal. But a "good" emulator does this based on the real signal from the sensor, adjusting it in the right direction, according to the algorithms programmed in the emulator. It also takes into account the specifics of the original sensor used and the manufacturer.

Installing the lambda emulator

Installation and connection of the lambda probe emulator is done in the engine compartment of the car, in places that are protected from high temperatures and moisture. In addition, this place should at the same time ensure ease of subsequent access to the device, because the operation of the device will need to be monitored, and if necessary, then adjustments. Typically, manufacturers / installers use the following connection color scheme:

• the blue conductor is connected to a gas / petrol switch or a relay (+ 12v must be supplied to the wire when the car is running on gas);
• the white conductor is connected to the vehicle ECU;
• the blue and white conductor connects directly to the lambda probe;
• the black conductor is connected to ground;

I am collecting questions about installing a lambda probe emulator, answering them along the way 🙂

1. Lambda probe emulator. Location of components on the board.

In order to avoid brainstorming, loss of time and errors in wiring the circuit, I give an image on which all components are signed, the polarity is indicated (when it is required) and the values \u200b\u200bof the components of the lambda emulator are indicated.

It is in this form that the board will appear in front of you after etching. Naturally, this is a rear view from the side of the tracks, keep this in mind as the components on this side will be soldered, and on the front side there will be 🙂

2. What lambda should I choose to install it with a lambda probe emulator?

It's up to you to choose on this topic. You need a zirconium one, that is, one that is available in any auto parts store. On the specialized forums of each machine, there are whole topics with an answer to this question. But I will write a few numbers later, these are the lambdas that people have and work in conjunction with the lambda probe trick.

3. How to properly install lambda snag?

At the time of this writing, there were two connection instruction images. The first is a photo of an unknown author, the second is mine) I am attaching.

Lambda probe emulator. Connection diagram.

Looking ahead, I'll say, the idea arose to record a video with the installation process of the emulator and comments. So far I do not promise anything on the timing, but I really hope that the video will be recorded with the arrival of the summer heat) We are waiting, monitoring)

By the way, the scheme given above will be supplemented well, just the other day ...

4. Vehicles on which it is possible to install a lambda probe emulator.

At this point, there will be a supplemented list. Supplemented by feedback, it means slow) You can always help if your car is not on the list.

How to determine the lambda on the car? Climb into the car with any pribluda, "sniffing" lambda and see the numbers or lambda graphs. Titanium lambda ranges from 0 to 5 volts, zirconium from 0 to 1 volts.

• Jeep Cherokee XJ. 1987-1991 years of release (onwards)
• Opel Vectra. ???? - ???? G.V.
• Hyundai V6 - ?????

The most important thing is feedback! If you have questions, write them in the comments, in the form feedback, on Drive, I will supplement the article for future readers)