20-22 Ford 6.7L Powerstroke Ford Downstream Nitrogen Oxide (NOx) Sensor

Fits: 2020-2022 Ford 6.7L Powerstroke 

It is the downstream NOx Sensor for your exhaust system. In a typical modern diesel exhaust after-treatment layout (SCR + DPF + catalyst), the downstream NOx sensor sits after the SCR/DPF system to monitor actual NOx emissions leaving the tailpipe.

The NOx sensor measures the concentration of nitrogen oxides (NO and NO₂ — generally grouped as “NOx”) in the exhaust gas. In diesel engines with an SCR (Selective Catalytic Reduction) system, sensors like this are critical to regulate and verify after-treatment performance. The downstream sensor’s main job is to verify that the exhaust emitted into the atmosphere meets emissions standards — i.e. to confirm the SCR/DPF system is doing its job in reducing NOx before exhaust exits the tailpipe. A failing or faulty NOx sensor can lead to increased emissions, failed emissions tests (where applicable), engine warning lights, or reduced efficiency of the emission-control system.

Because this is a downstream sensor, ensure the rest of your emission system (SCR catalyst, DPF, exhaust piping) is in good condition — a damaged aftertreatment system can affect sensor readings and overall emissions compliance. After installing a new NOx sensor, you may need to clear any fault codes and possibly allow the vehicle’s control module to recalibrate the emissions control system (depending on how the vehicle is built). As with most exhaust-system sensors, be careful handling the sensor tip and don’t over-tighten when installing (use correct torque) to avoid damage.

Ford: LC3Z-5L216-C