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EmissionsSeverity Medium: diagnose soon

P242FDiesel Particulate Filter Restriction – Ash Accumulation

What it means

The particulate filter contains so much ash (which regeneration can't burn) that it is restricted. Ash builds up over the life of the filter, faster with oil consumption or the wrong oil.

Symptoms

  • Loss of power or limp mode
  • Radiator fan running after switch-off (regeneration)
  • Higher fuel consumption
  • DPF warning light

Common causes

  • High mileage filter full of ash
  • Engine burning oil
  • Wrong (high-ash) engine oil

What to check first

  1. Read the ash load or distance since the DPF was replaced
  2. Check oil consumption and the oil specification
  3. Clean or replace the filter and reset the ash counter
Can I drive with P242F? Usually yes for a short distance, but performance or economy may suffer and the fault can get worse. Diagnose it soon.

Generic OBD-II meaning. Manufacturer-specific meanings and checks can differ; always check the service information for the car.

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P242F: questions and answers

What does P242F mean?

P242F: Diesel Particulate Filter Restriction – Ash Accumulation. The particulate filter contains so much ash (which regeneration can't burn) that it is restricted. Ash builds up over the life of the filter, faster with oil consumption or the wrong oil.

What are the symptoms of P242F?

Loss of power or limp mode. Radiator fan running after switch-off (regeneration). Higher fuel consumption. DPF warning light.

What causes P242F?

High mileage filter full of ash. Engine burning oil. Wrong (high-ash) engine oil.

How do you diagnose P242F?

1. Read the ash load or distance since the DPF was replaced 2. Check oil consumption and the oil specification 3. Clean or replace the filter and reset the ash counter

Can I drive with P242F?

Usually yes for a short distance, but performance or economy may suffer and the fault can get worse. Diagnose it soon.