Nox Sensor Blog

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Nox Sensors, Audi, BMW, Mercedes, VW problems. 

We have had a volume of calls regarding Nox Sensor faults, we have decided to construct a blog. If you need further help or information click here.

What happens when the NOx sensor fails?

If a NOx sensor fails, the vehicle can have multiple faults on the dashboard which will put your car into limp mode. NOx sensors are directly linked to the SCR system. There will also be emission and general SCR system faults. These faults include increased fuel consumption, unstable and erratic idle all these are signs that the Nox Sensor could be malfunctioning. 

What exactly is a NOx sensor and what does it do

The sensor is normally mounted on the exhaust system before the catalytic converter. The sensor measures the level of nitrogen oxide for the engine’s computer so adjusts valve timing and fuel mixture.

BMW NOx sensor for N43/N53 fault codes 

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Deleting/clearing the adaptations of the NOx sensor is critical. If you fail to clear them after regeneration you may have error codes. Further error messages such as the 30D6, and 30DE. The sensor should be coded to the Ecu.

Adblue Nox sensor issues with Audi

Our technical Director Lee has seen many AdBlue errors related to Nox Sensor faults. Most people are unaware that the AdBlue system on most cars especially Audi uses the NOX sensor as an input to ascertain how much AdBlue is required to be injected. Once this sensor plays up you would most likely have the sensor replaced. Here at Auto Assist, we offer the most competitive prices on replacing NOx sensors.


About Auto Assist Group: From large multinational blue-chip companies to small independent business right down to the end-user we understand your needs. With a nationwide service, powered by Xpart, a global buying force that sets us apart from the rest. So whether you use AdBlue Assist, DPF Assist Fuel Assist, or Garage Assist, our sole aim is to exceed customer expectations. Established since 2009, we have earned a well-deserved reputation for outstanding technical know-how, service and value. If you would like more information or would like to book in your car please call our call 03300100411.


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