Diesel Trouble Codes

P2459 — Diesel Particulate Filter Regeneration Frequency (6.7 Power Stroke)

P2459 on 6.7 Powerstroke means regenerations are occurring more often than expected. Diagnose why soot load is high or regeneration control is being triggered…

Updated September 1, 2026

What it means

Regenerations are occurring more often than expected.1

Most likely causes

  1. Excess soot production from engine faults — Injector, EGR, turbo, or air-leak faults increase soot, raising DPF load and regeneration frequency.1
  2. Frequent short trips and extended idling — Lots of short-trip idling prevents complete regeneration and raises frequency.1
  3. DPF differential-pressure sensor or sample-tube issue affecting regeneration decisions — DPF differential-pressure sensor circuit fault or implausible signal can influence regeneration control.23
  4. Boost / turbo performance problem increasing soot — Actual boost not tracking desired boost can increase soot production.4
  5. DPF hardware failure leading to repeated regeneration attempts — Field reports link DPF failure with repeated regeneration issues and limp behavior on 6.7 Powerstroke trucks.56

How to diagnose

  1. Verify freeze-frame and monitor DPF soot load and distance-since-last-regen with a scan tool.
  2. Inspect driving pattern history for short trips / extended idle; correlate with high regen frequency.
  3. Check for accompanying codes for injectors, EGR, turbo/boost, air intake leaks.
  4. Test DPF differential-pressure sensor circuit and sample tubes for faults, drift, blockage or leaks.
  5. Review live data for boost actual vs desired and turbo actuator operation.
  6. If no engine or sensor faults are found and regen frequency remains high, evaluate DPF condition per manufacturer procedures.

Parts and tools you may need

Rough cost and difficulty

Diagnostic labor varies by shop; DPF or turbo replacement costs are high. Field reports cite DPF replacement and turbo replacement on affected trucks.

When to see a pro

DPF service and high-pressure fuel system work require specialized tools and safety precautions. Have a qualified diesel technician perform diagnosis and repairs.

Sources

  1. Curated DTC seed — 6.7 Powerstroke (curated) ↩︎ ↩︎ ↩︎

  2. Curated DTC seed — 6.7 Powerstroke (curated) ↩︎

  3. Curated DTC seed — 6.7 Powerstroke (curated) ↩︎

  4. Curated DTC seed — 6.7 Powerstroke (curated) ↩︎

  5. NHTSA owner report 11521728 ↩︎

  6. NHTSA owner report 11654583 ↩︎

Watch a repair

Third-party videos, not ours — for illustration. Confirm anything against the factory service information for your truck.

Is My DPF Failing?! Code P2459 On A 6.7 Powerstroke — Power Stroke Maintenance