The NOx sensor (nitrogen oxide sensor) monitors the level of nitrogen oxide gases in your vehicle’s exhaust stream. It’s a key component in the emissions control system on most modern diesel vehicles, working alongside the SCR system and AdBlue to ensure exhaust gases meet legal emissions standards. When it fails, the vehicle’s emissions management is compromised, and the engine management system will typically flag a fault.
A faulty NOx sensor will almost always trigger a warning light and can cause the vehicle to enter a reduced performance mode. Left unresolved, it can also lead to increased AdBlue consumption, further emissions faults, and a failed MOT.
NOx sensor faults need to be properly diagnosed before replacement is carried out. In some cases, what appears to be a sensor fault is actually a fault elsewhere in the emissions system, and replacing the sensor won’t resolve the underlying issue. We carry out a full diagnostic assessment first, confirm the fault, and then carry out the repair correctly.
NOx sensors vary in specification between makes and models and using the correct part for your vehicle matters. We source appropriate quality components and carry out any necessary system recalibration after replacement.
Keep your engine running efficiently by booking your NOx sensor replacement with CCM today.
CCM has been trusted by customers across Surrey and Sussex for over 30 years, and recognised by the industry to match, with awards including back-to-back Automechanika Best Multi-Site Garage wins, consecutive IGA Best Independent Garage titles, and the Top Garage Award 2025.
To book your NOx Sensor Repair in Ewhurst, Gatwick or Cranleigh, use our online booking or contact us online. Alternatively, give us a ring.
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