Buy wp20132 - Genuine Cummins Inlet NOx Sensor EPA10 - wisentpartscenter.com

Description

4326863RX is a Genuine Cummins inlet NOx sensor for select EPA10 Cummins aftertreatment systems. This is the upstream NOx sensor used before the SCR catalyst to report incoming NOx levels to the aftertreatment control system. The ECM/ACM uses this reading to compare inlet and outlet NOx values, monitor SCR efficiency, and control emissions-related diagnostics. Verify 4326863RX by ESN, original sensor number, sensor location, connector style, harness length, and the cross-reference / supersession list shown on this page. A wrong or low-quality NOx sensor can create repeat SCR faults, false NOx readings, failed aftertreatment tests, and unnecessary derate diagnostics.

Purpose of the Part

The inlet NOx sensor measures nitrogen oxide levels in the exhaust stream before SCR reduction takes place. It helps the control system determine whether the SCR system is reducing NOx correctly when compared with the outlet NOx sensor. If the inlet sensor reads wrong, drops communication, or fails its heater circuit, the truck may set SCR efficiency faults or enter an emissions derate even when other SCR parts are working.

Issue Symptoms / When to Replace

Common signs that 4326863RX may need inspection or replacement include:

  • Check engine light or aftertreatment warning light
  • SCR efficiency or NOx conversion faults
  • Inlet NOx reading stuck, slow to respond, or not matching operating conditions
  • Failed aftertreatment test after DEF quality, dosing, and outlet NOx sensor are checked
  • Derate or inducement related to SCR/NOx monitoring
  • Damaged sensor harness, melted wiring, loose connector, or corrosion at the sensor module
  • Sensor heater or power supply faults

Possible related intake NOx fault examples may include Cummins fault codes 1885, 3649, 3682, 3718, 3725, and 3748, depending on ECM calibration and application. These codes do not confirm the sensor is bad by themselves. Wiring, power supply, CAN/data link, DEF quality, exhaust leaks, dosing issues, or SCR catalyst problems should be checked before replacing the sensor.

Brand Information

Cummins is the OEM engine and aftertreatment supplier for many EPA10 diesel platforms. For NOx sensors, Genuine Cummins is preferred because the sensor, module, connector, and programming must match the aftertreatment system correctly. A cheaper sensor can cost more if it causes repeat SCR faults, failed regen/SCR tests, or another shop visit for the same derate.

Installation Notes

Before replacing 4326863RX, confirm the sensor is the inlet/upstream NOx sensor and not the outlet/downstream sensor. Let the exhaust cool, disconnect power if required, unplug the sensor module, and remove the probe from the exhaust bung with the correct sensor socket or wrench. Compare the old and new sensor, route the harness the same way, and keep the wiring away from heat and sharp edges. After installation, clear faults only after the repair is verified and run the required Cummins INSITE / OEM aftertreatment test if needed. Refer to Cummins QuickServe for torque specs and final procedure.

How to Identify an OEM Part

A Genuine Cummins 4326863RX inlet NOx sensor should be verified by the Cummins label, original packaging, supplier/module markings, connector shape, harness length, and probe configuration. Match the removed sensor to 4326863RX and to the cross-reference / supersession list shown on this product page. Some related numbers may appear with or without dashes or spaces, so compare the full number carefully before ordering.

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    Verify fitment
    Send VIN/ESN and we’ll confirm.

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Warranty & Return Information
Warranty Information

Wisent Parts offers a 180-day warranty on all parts from the date of delivery. This warranty covers orders placed directly through our website. If a part fails during this period, we’re here to help - whether it’s a replacement, repair, or refund. For full details, refer to the Warranty page.

Return Information

All electrical parts and final sale items are non-refundable and cannot be returned. Please double-check compatibility before purchase. If you have questions, our support team is here to help before you place your order.