Description
NOx Nitrogen Oxide Sensor 5WK96674A — OEM-Grade Emissions Control Replacement
The iFJF NOx Sensor 5WK96674A is a direct plug-and-play replacement for your vehicle's factory nitrogen oxide sensor. Engineered to meet or exceed OEM specifications, this sensor restores proper DEF/SCR system function, eliminates check engine lights triggered by NOx sensor fault codes, and helps your diesel engine pass emissions testing.
What a NOx Sensor Does
Nitrogen Oxide (NOx) sensors monitor the concentration of harmful nitrogen oxides in your diesel exhaust stream — both before and after the Selective Catalytic Reduction (SCR) catalyst. The engine control module (ECM) uses this data to precisely meter Diesel Exhaust Fluid (DEF) injection. When a NOx sensor fails, the ECM can't regulate DEF dosing properly, leading to increased emissions, reduced fuel economy, and potential limp-mode activation.
Key Features
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OE-Equivalent Performance — Calibrated to match the voltage curve and response time of the factory sensor for seamless ECM integration.
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Plug-and-Play Installation — Pre-terminated connector matches factory wiring harness. No splicing, no programming — remove the old sensor and install the new one.
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Durable Construction — High-temperature ceramic sensing element with stainless steel probe body withstands exhaust temperatures up to 930°C (1,700°F).
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Clears NOx-Related Fault Codes — Resolves common DTCs related to NOx sensor performance, circuit range, and rationality errors.
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12-Month Warranty — Backed by iFJF's quality guarantee against manufacturing defects.
Compatibility
| Make |
Models |
OEM Ref |
| Kenworth |
Multiple Class 8 models |
2871978 |
| Peterbilt |
Multiple Class 8 models |
2894939RX |
| Van Hool |
Commercial Bus |
2871978 |
Cross-Reference / OEM Part Numbers
| Manufacturer |
Part Number(s) |
| Kenworth/Peterbilt/Van Hool |
2871978, 2894939RX |
| Continental/VDO |
5WK96674A |
Specifications
| Sensor Type |
Nitrogen Oxide (NOx) |
| Sensor Model |
5WK96674A |
| Connector Type |
Pre-Terminated Factory Match |
| Probe Material |
Stainless Steel with Ceramic Element |
| Operating Temperature |
Up to 930°C (1,700°F) |
| Installation |
Plug-and-Play (No Programming) |
| Warranty |
12 Months |
Symptoms of a Failing NOx Sensor
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Check Engine Light (CEL/MIL) — Common fault codes: P2200-P2214 (NOx sensor circuit), P229E/P20EE (SCR NOx efficiency)
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Failed Emissions Test — Vehicle produces excessive NOx emissions during inspection
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Increased DEF Consumption — ECM overcuts DEF trying to compensate for bad sensor readings
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Reduced Fuel Economy — Engine may run in a less efficient mode when NOx sensor data is unreliable
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Limp Mode / Reduced Power — In severe cases, the ECM may limit engine power to protect the emissions system
Frequently Asked Questions
Do I need to reprogram the ECM after installing this sensor?
No — this is a plug-and-play sensor. The ECM will automatically recognize the new sensor on the next key cycle. However, you may need to clear existing fault codes with an OBD-II scanner. Some vehicles require a short drive cycle (10-20 miles) for the sensor to fully calibrate and for readiness monitors to set.
How do I know if my NOx sensor needs replacement?
The most common indicators are: (1) check engine light with NOx-related DTCs, (2) failed emissions test with high NOx readings, and (3) visible physical damage to the sensor or wiring harness. A professional diesel shop can confirm the diagnosis with a scan tool by comparing upstream and downstream NOx readings.
What's the difference between upstream and downstream NOx sensors?
Upstream (pre-SCR) sensors measure NOx entering the catalyst. Downstream (post-SCR) sensors measure NOx exiting the catalyst. They may look identical physically but are typically calibrated differently. Verify your vehicle's exact position before ordering.
Can a bad NOx sensor cause DEF system problems?
Yes — the ECM relies on NOx sensor data to calculate DEF injection rates. A faulty sensor sending incorrect data can cause over-injection (wasting DEF fluid) or under-injection (failing emissions standards). Either scenario can trigger additional fault codes.
How long should a NOx sensor last?
Factory NOx sensors typically last 80,000-150,000 miles depending on driving conditions. Contaminated DEF fluid, excessive idling, and high-sulfur fuel can significantly reduce sensor life. If one sensor has failed, the others on the vehicle may not be far behind.
