NOx sensors
If the sensors detect that too much NOx is being emitted, they tell the SCR system so it can adjust the urea amounts accordingly. So their function is to monitor the NOx conversion efficiency of the catalyst. The sensors can work as part of a feedback loop to the emissions system control unit to make real-time adjustments to optimise NOx conversion. The control unit can then make adjustments to optimise NOx conversion performance. Most common aftertreatment systems have two NOx sensors: one 'upstream' on the turbo side of your particulate filter (DPF) and the second 'downstream', on the exhaust side of your catalytic converter (DOC). The two signals, sent directly to your engine control module, are then compared to determine the 'conversion efficiency' of your exhaust system. In the case of SCR technology, feedback can also be provided to the urea dosing system, while in the case of lean NOx trap catalysts, a feedback loop could signal the regeneration of the trap.
The NOx sensor has a dual chamber design that measures both oxygen and NOx levels. When exhaust gas enters the sensor, the oxygen is pumped out and the NOx finds its way into a second chamber where the gas is exposed to a catalyst that calculates and reports this information to your computer.
If you are thinking of changing your DPF (Diesel Particulate Filter) or DOC (Diesel Oxidation Catalyst), you should also think about replacing the NOx sensors to keep everything running smoothly. This is where we come in. We currently stock NOx sensors for almost all European applications, and many more vehicle applications are already in the pipeline.
What is a NOx sensor?
The NOx sensor is a sensor that measures the concentration of nitrogen oxides in the exhaust gas. The purpose of the NOx sensor is to ensure that the NOx emitted by the vehicle is within the legal limits. These are usually vehicles with the Euro5 and Euro6 emissions standards.
Nitrogen oxides are harmful exhaust gases that can cause air pollution and health problems.
NOx sensors are installed in the exhaust systems of modern diesel vehicles and some petrol engines. They are usually placed near the catalytic converter or in the exhaust gas recirculation system. Some vehicles also have multiple NOx sensors to ensure accurate monitoring of tailpipe emissions. These are then located before and after the catalytic converter.
Euro Standards
European standards (Euro1-6) set limits on the emission of nitrogen oxides and other harmful exhaust gases. NOx sensors are used to ensure that exhaust emissions are within these limits. Different types of NOx sensors are available depending on the European standards and vehicle type.