Diesel Trouble Codes

P2002 — Diesel Particulate Filter Efficiency Below Threshold (Bank 1) (6.7 Power Stroke)

Diagnostic reference for P2002 on 6.7 Powerstroke.

Updated September 1, 2026

What it means

The PCM judges DPF filtering efficiency, using pressure/temperature data, to be below threshold.1

Most likely causes

  1. Cracked or ash-loaded DPF — Physical DPF degradation or ash accumulation reduces filtration efficiency.1
  2. Failed differential-pressure sensor or plugged sample tubes — Incorrect pressure readings cause the PCM to calculate low efficiency.12
  3. Repeated interrupted regenerations — Frequent aborted regens increase soot loading and lower measured efficiency.1
  4. Excess soot production from engine faults — More soot reaches the DPF, raising differential pressure and triggering efficiency codes.3
  5. DPF differential-pressure sensor circuit fault — Circuit fault for sensor A can corrupt efficiency calculations.2

How to diagnose

  1. Verify freeze-frame and related codes; look for P2452, P2459, P0299, P0234.
  2. Inspect DPF differential-pressure sensor, sample tubes, and wiring/connector for damage, plugging, or corrosion.
  3. Review regeneration history and driving pattern for repeated interrupted regens.
  4. Check for conditions that increase soot production, such as frequent short trips/idling or engine faults that raise soot.
  5. Assess DPF condition for cracking or ash loading based on pressure/temperature data and service history.

Parts and tools you may need

Rough cost and difficulty

Costs vary by region and labor; obtain local quotes.

When to see a pro

If diagnosis points to internal DPF failure, high-pressure fuel system work, or requires removal of safety-critical aftertreatment components, have a qualified diesel technician perform inspection and repair.

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) ↩︎

Watch a repair

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

2017-2020 Super Duty 6.7 Powerstroke Code P2002 Fix. WITH PARTS LIST #newtoyou #powerstroke — Bearded Ford Tech