4326870RX | Genuine Cummins Nitrogen Oxide (NOx) Sensor

The Genuine OEM Cummins Nitrogen Oxide Sensor, part number 4326870RX, is designed to measure nitrogen oxide (NOx) levels in the exhaust of compatible heavy-duty diesel engines. The sensor provides emissions data to the engine and aftertreatment control systems to help monitor exhaust emissions and SCR system performance.

PRODUCT INFORMATION

• Part Number: 4326870RX

• Brand: Cummins

• Part Name: Nitrogen Oxide (NOx) Sensor

• System: Exhaust Aftertreatment / Emissions Control

• Sensor Position: Verify inlet or upstream position before installation

• Condition: Confirm the actual item condition before publishing

APPLICATIONS

This part number is associated with selected Cummins ISX engine applications and certain heavy-duty trucks equipped with compatible Cummins engines. Applications may include vehicles from manufacturers such as Freightliner, Kenworth, Peterbilt, International, Volvo, and Western Star. Exact fitment depends on the engine, emissions configuration, and sensor position.

FUNCTION

The NOx sensor measures nitrogen oxide concentration in the exhaust and sends data to the engine control system. These readings help the emissions system monitor NOx levels and manage aftertreatment operation.

COMMON SIGNS OF SENSOR FAILURE

• Check engine or emissions warning lights

• NOx sensor or SCR-related fault codes

• Implausible or inconsistent NOx readings

• Sensor heater or electrical circuit faults

• Possible engine derate related to an emissions system fault

These symptoms may have other causes and should be confirmed through diagnostics.

WHY REPLACE

A faulty NOx sensor can provide inaccurate emissions readings and interfere with aftertreatment monitoring. Replacing a confirmed defective sensor with the correct part helps restore reliable NOx measurement and emissions system operation.

FITMENT INFORMATION

Part number 4326870RX is associated with selected Cummins engine and heavy-duty truck applications. Verify the original part number, engine serial number, emissions system, connector, and sensor position before ordering. Inlet and outlet NOx sensors are not necessarily interchangeable.

GENUINE CUMMINS PART

This listing identifies OEM part number 4326870RX, a Genuine Cummins Nitrogen Oxide Sensor for compatible diesel engine exhaust aftertreatment systems.