Powertrain, generic (extended)

P242F Particulate Filter Restriction - Ash Accumulation (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P242F reports that so much incombustible ash has collected in the bank 1 particulate filter that it restricts flow and no regeneration can clear it. Ash comes mainly from oil additives, builds up over the service life and leaves the filter only through cleaning or replacement. Deutz stores P242F-00 as a high ash load warning on its EMR L1 controller. GM's 2018 diesel tables watch for the same condition but file it under P24A4, which GM labels ash accumulation: a filtered flow resistance from differential pressure and exhaust flow, 5 failures in 10 samples, Type A. On 2015 Ram 2500/3500 with the 6.7 L Cummins, Stellantis issued PCM software (18-037-16) because P242F could set with no defect present, so check the calibration first. Soot overload belongs to P2463; the second filter has P243A.

Likely causes

Filter has reached its ash capacity after high mileage or operating hours
High oil consumption or unsuitable oil (high ash content) speeding up ash build-up
Calibration setting the code without a defect (Ram 6.7 L 2015, bulletin 18-037-16)
Differential pressure sensor or hoses reporting too much restriction

Symptoms

  • MIL or DPF service message
  • Regenerations becoming more frequent
  • Loss of power at high load due to back pressure

Repair estimate

DifficultyHardWorkshop job
Parts and labour€0–3,000
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

What to check first

  1. Check ash load value
  2. Check oil specification
  3. DPF cleaning or replacement

Parts involved

dpf b1

Related codes

P243AP2463P24A4P2459P2002

References: serdia.deutz.com, gsi.ext.gm.com, static.nhtsa.gov.