AI Diesel Tech
P2003OBD-IIAFTERTREATMENT

Diesel Particulate Filter Efficiency Below Threshold (Bank 2)

Common Symptoms

  • Check engine light illuminated
  • Reduced engine power or derate
  • Excessive black smoke from exhaust
  • Poor fuel economy
  • DPF regeneration cycles more frequently than normal
  • Strong diesel odor from exhaust

Most Likely Root Causes

  • Clogged or damaged diesel particulate filter
  • Failed DPF differential pressure sensor
  • Exhaust leaks upstream of DPF
  • Faulty DPF temperature sensors
  • Engine oil contamination in DPF from excessive oil consumption

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Component Location

The diesel particulate filter is located in the exhaust system downstream of the turbocharger and DOC, typically under the vehicle chassis.

Manufacturer Notes

Bank 2 designation typically applies to multi-bank diesel engines such as V-configuration heavy-duty platforms with dual aftertreatment systems.

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