Lambda probe measures the oxygen in the flue gas with reference to atmospheric oxygen and because of this control unit the amount of air and fuel can be regulated with greater precision up to a 14.7 to 1, contributing to the better use of fuel combustion and less pollution to the environment through the control of the exhaust.
Located in the exhaust pipe of the car is the placement, which is best suited to operate and this is independent of whatever the engine speed. The optimum operating temperature of the probe is about 300° C or more.
A part of the Lambda probe is always in contact with the air of the atmosphere which is outside the exhaust pipe, while part of it will be with the exhaust gases produced by combustion.
Its operation is based on two platinum electrodes, one in contact with air and other in contact with gases, separated by a ceramic electrolyte. The oxygen ions are collected by the electrodes and one must remember that each of the electrodes are in different locations, one in the air atmosphere and other in the place for gases to escape, thus creating a voltage difference between the two, consisting at a voltage of 0 to 1 volt.
Giving a difference between the two sections of oxygen probe sends a voltage to the control unit so that it regulates the amount of fuel spray.
Cables Lambda probe:
Lambda probes may have different number of cables with 1, 2, 3 or 4 cables.
Only cable 1 show it in black to give power to the probe, the mass is achieved by the single case of it.
Probes 3 or 4 cables are possessing resistance heating and these probes are usually white wires which are responsible for feeding the heating probe with positive mass.
The extra wire in the 4-wire lambda is the mass of the oxygen sensor and is usually gray.
Typical failures:
The consequences of faulty lambda probe can find the power of witness Check Engine, a high consumption of fuel, and in the presence of charcoal and smoke candles.
Obviously these failures are not always caused by a faulty lambda probe, but it is possible that these symptoms were given to them.
According to the manufacturer of the probe there are recommendations on replacing them every few thousand miles, and it is a good practice to check the exhaust and lambda probe test every 20,000 or 30,000 miles.
Remember that a lambda probe in poor condition can cause excessive consumption of fuel, making it ideal to be assured that the probe is functioning properly.