Description:
A Diesel Exhaust Fluid Pump 4387658  is a component of a diesel engine’s Selective Catalytic Reduction (SCR) system, which is used to reduce nitrogen oxide (NOx) emissions from the exhaust. It’s sometimes also called a urea dosing module because it handles Diesel Exhaust Fluid (DEF), which is a urea solution. Denoxtronic 2.2 AdBlue Doser Fluid Supply Module 24V, 3 Outlet For Cummins Engines EPA10/13 15 liter ISX/QSX

Part Number: 4387658 
Condition: New
Manufacture/Brand: Cummins
Related Part Numbers: 4387658CUM, 4387658NX, 4387658RX

Fits 4387658 For Cummins Engines XPI fuel systems on EPA10/13 Automotive 15 liter ISX/QSX 24V, 3 Outlet

 B4.5 CM2350 B129B, B4.5 CM2350 B147B, B6.7 CM2350 B135B, B6.7 CM2350 B148B, F3.8 CM2350 F132B, ISB6.7 CM2350 B101, ISBE4 CM850, ISF3.8 CM2220, ISF3.8 CM2220 AN, ISF3.8 CM2220 F116, ISF3.8 CM2220 IAN, ISL9 CM2350 L101, ISX12 CM2350 X102, ISX12 CM2250, ISX11.9 CM2250, L9 CM2350 L119B, QSB4.5 CM2350 B106, QSB4.5 CM2350 B122, QSB6.7 CM2350 B105, QSB6.7 CM2350 B112, QSB6.7 CM2350 B130, QSL9 CM2350 L102, QSL9 CM2350 L107, QSL9 CM2350 L118, QSX15 CM570


Purpose of using 4387658:

  • Reduce NOx Emissions

    • Injects the right amount of DEF into the exhaust, which reacts in the SCR (Selective Catalytic Reduction) catalyst to convert harmful NOx into harmless nitrogen (N₂) and water (H₂O).

  • Meet Emission Regulations

    • Ensures compliance with strict standards such as Euro 6, EPA Tier 4 Final, and other regional diesel emission laws.

  • Protect the Environment and Health

    • Reduces smog-forming NOx pollutants, protecting air quality and reducing respiratory hazards.

  • Support Engine Efficiency

    • By controlling NOx chemically instead of mechanically limiting combustion, the engine can operate efficiently without sacrificing power.

  • Enable Precise DEF Usage

    • The module ensures exact dosing, preventing overuse of DEF (wasteful) or underuse (ineffective emission reduction).


Signs of Bad Diesel Exhaust Fluid Pump 4387658:

  • DEF/AdBlue Warning Light

    • Dashboard lights may indicate low DEF flow, system malfunction, or dosing errors.

  • Check Engine Light or SCR Fault Codes

    • The ECU may detect improper dosing and trigger engine fault codes.

  • Reduced Engine Power (Limp Mode)

    • Many modern diesel engines limit power to protect the engine when the SCR system is not functioning correctly.

  • Increased NOx Emissions / Failed Emissions Test

    • A malfunctioning doser module can prevent proper NOx reduction, causing failed emissions inspections.

  • Frequent or Failed SCR Regeneration

    • If DEF is not being injected correctly, the SCR catalyst cannot reduce NOx efficiently, leading to repeated regeneration attempts or failure.

  • Unusual DEF Usage

    • Overuse (leak or over-injection) or underuse (blockage or pump failure) of DEF can indicate a problem with the module.

  • Strange Noises from Module

    • A failing pump inside the doser module may produce unusual buzzing or grinding sounds.