AI Diesel Tech
P2459OBD-IIAFTERTREATMENT

Diesel Particulate Filter Regeneration Frequency

Common Symptoms

  • Check engine light or DPF warning light illuminated
  • Frequent DPF regeneration cycles
  • Reduced fuel economy
  • Loss of engine power or reduced performance
  • Strong exhaust odor during regeneration
  • Excessive exhaust smoke during regeneration

Most Likely Root Causes

  • Faulty differential pressure sensor
  • Clogged or contaminated DPF
  • Failed DPF temperature sensors
  • Exhaust leaks upstream of DPF
  • Excessive oil consumption contaminating DPF

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Component Location

The DPF is located in the exhaust system downstream of the turbocharger and upstream of the tailpipe, typically underneath the vehicle.

Manufacturer Notes

Excessive short-trip driving or prolonged idling can prevent proper DPF regeneration and trigger this code on many diesel platforms.

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