In the world, the number of motor vehicles is growing every year, with which the amount of harmful emissions into the atmosphere from working engines increases. In this regard, significantly increased requirements for manufacturers of transport on environmental performance. Such an approach makes it necessary to find effective solutions to minimize emissions toxicity.
One of the evolutionary methods is the modernization of exhaust exhaust systems. The process uses catalytic converters. Such modules help to neutralize hazardous aggressive chemical compounds present in the exhaust. However, the failure of such units is fraught with expensive repairs. This forces domestic car owners to look for an opportunity to deceive the lambda probe.
- 1 The essence of the problem
- 2 Failure
- 3 Structural features of the sensor
- 4 Types of compensators
- 5 Sensor Emulation
The essence of the problem
On the dashboard of modern cars, the Check Engine indicator light in some cases demonstrates the failure of an oxygen sensor, which motorists call a lambda probe. Depending on the model of car, the manufacturer can install them from two to four pieces.
To determine which of them in reality is swallowing, only the autoscanner of errors helps. If we ignore the signals of malfunction, then soon there may be a problem with the efficiency of the catalytic converter. In advanced cars, its replacement can cost more than a dozen thousand rubles.
Otherwise, the catalyst in the car could already become useless or be removed by the previous owner of the foreign car. This also happens if the owner of the car does not want to spend a large amount for costly repair of the problem node. Many craftsmen rescues snag lambda probe with their own hands, made for their own cars.
If you do not do it, then there will be problems with the performance of the machine. It is necessary to bypass the lambda probe, because otherwise it will send commands to the computer unit (ECU), indicating violations with exhaust gases. Based on the data received, the injection control computer will interpret the information as if the engine is running on a lean mixture. With this algorithm, the ECU will significantly add fuel supply, filling it with nozzles.
With this approach, the dynamic acceleration parameters of the power plant will decrease, and the fuel consumption will increase significantly. Dips in the engine idling will also appear. Emissions of CO into the atmosphere will begin to reach critical parameters of 3-5%, and the rate for them is no more than 0.5%.
Before you do the snag lambda probe with your own hands, you should know the real reasons why the node is broken. The most common factors include such events as:
- the engine runs on low compression;
- A problem will appear when using leaded gasoline, as the constituents (lead compounds, sulfur, silicone elements) contribute to the intensive destruction of oxygen sensors;
- an open circuit may occur in the area of the power cable, leading to the on-board circuit closure;
- a faulty ignition system is able to overheat the sensor, leading to undesirable consequences;
- sometimes there is physical damage to the node;
- sensor life exceeded.
It is worth considering that the average recommended duration of testing the oxygen sensor is about 30 thousand kilometers.
In most cases, removing the knot so that the electronic snag of the lambda probe was mounted with its own hands instead of it, is quite simple. An alternative can be a flame arrester mounted on the same place. The advantages of the latter usually include the following facts:
- long service life;
- minimum cost;
- effective reliable operation.
However, the minus of the flame arrester is a significant deterioration in the environmental parameters of the car. If a driver plans to go on a foreign trip with his car, then he should be aware of the excess emission standards of his modified vehicle, which is fraught with high fines.
Structural features of the sensor
The scheme of a lambda probe snagging with your own hands implies its removal from the design of the car. To detect this block, you need to know what it looks like. Usually this device is a cylindrical metal element to which the cable is connected.
On the shell of the probe has a coating of precious metal - platinum. This affects the cost of the site. Inside there is such a device:
- metal contact connecting the cables to the electrical part of the sensor;
- dielectric protective seal that is equipped with an air hole;
- hidden zirconium electrode protected by a ceramic tip, since during operation the metal part can overheat up to 1000WITH;
- protective shield with exhaust port for exhaust gases.
In modern cars there are two types of sensors:
- two-point version;
- broadband products.
Although their types are different, but the internal structure, as well as external parameters, is quite similar. The difference lies in the functioning of the devices. The development of two-point technology is the result in the form of broadband products.
The sensors are equipped with an injection element that sends signals to the computer due to changes in voltage fluctuations. In this case, the supply of current increases or decreases. This occurs on the basis of a small amount of air that has penetrated into the technological gap for measuring the concentration of CO.
Also, sensors are differentiated by other features:
- without heating - equipped with one wire and designed for operation 50-80 thousand km;
- heated - has 2.3 or 4 cables connected and requires replacement after 100 thousand km;
- Glider - two-element current limit sensor will need to be replaced after not less than 160 km.
The deception of an oxygen sensor will need to be supplied for an inoperative probe not only when it is broken, but also when the catalyst is working. It should be borne in mind that the repair of sensors in most cases is not provided.
Varieties of compensators
The most primitive and affordable option - mechanical spacer under the lambda probe. It is grinded in the form of an adapter, inside which is mounted a sensor with a mini-catalyst. Next, the entire unit is mounted back to its workplace.
In the process of self-assembly / disassembly, it is necessary to use a special end head with a technological groove or hole that does not allow damage to the product. Also in the head there must be a stiffener to ensure the strength of the structure. This is due to the fact that the screwed-in sensor is attached to its socket.
It is necessary to take into account that a change in the monitoring process is taking place after the assembled emulator of the lambda probe appears in the system with its own hands, the scheme of which implies the presence of ceramic chips inside. The latter is covered with a catalytic layer. After penetration through a small window into the catalyst and contact with the composition there, the concentration of gases present there with CO decreases. This is perceived by the ECU as normal operation of the standard device.
Below we present a dimensional drawing of a mechanical snag lambda probe.
Mechanical drawing of a lambda probe
The deception can be made independently, which will require the ability to work on a lathe and the presence of a metal billet. Many people get out of the situation simply by buying a ready-made replacement sample, which, depending on the model of car, will cost about 1000 rubles.
As an electronic replacement for the sensor, a block is used with a microprocessor connected to the wiring through which communication with the ECU is effected. The main purpose of emulation is to deceive automotive electronics by converting a real signal into a signal perceived by a computer as if from a normally working device.
You can use the most common schemes of such devices. However, at the initial stage it is necessary to carry out diagnostics on an oscilloscope with the sensor working properly.
Given the magnitude of the pulse, the appropriate capacitor and resistor are selected in the current circuit. Next, the corrected node is mounted in a thermotube and poured with molten poxypol. Connection is carried out through four removed wires.
Before starting all work on the connection, it is necessary to open the negative contact from the battery. This will protect all elements of the chain.