P242F fault code: what it means

P242F: DPF restricted or clogged with ash. Usually needs a DPF clean or replacement, and correct ECU software for the DPF fitted.

Engine and gearbox (powertrain) · Costly if missed

Usual causes, most likely first

ash-loaded / clogged DPF
failed DPF
wrong ECU software for the DPF type (e.g. Crafter)

P242F by make

Audi

DPF restricted or clogged with ash. Usually needs a DPF clean or replacement, and correct ECU software for the DPF fitted.

Usual causes: ash-loaded / clogged DPF; failed DPF; wrong ECU software for the DPF type (e.g. Crafter)

Ford

DPF restriction from ash build-up: unburnable ash fills the filter over time and regens no longer clear it.

Usual causes: high-km DPF full of ash; wrong (non low-ash) engine oil; oil burning from turbo or engine wear

GWM

DPF restricted by ash. Needs cleaning or replacing.

Usual causes: high-mileage ash loading; oil consumption; wrong engine oil

Isuzu

DPD restricted by ash. The filter needs cleaning or replacing.

Usual causes: high-mileage ash loading; oil consumption; wrong engine oil (not low-ash)

Jeep

DPF restricted by ash. Filter needs cleaning or replacing.

Usual causes: high-mileage ash loading; oil consumption; wrong engine oil

Land Rover

DPF restriction from ash build-up. The filter is full of ash that regeneration cannot burn off; the DPF needs cleaning or replacing.

Usual causes: high mileage ash loading; high oil consumption; wrong engine oil (not low-ash)

LDV

DPF restricted by ash. Needs cleaning or replacing.

Usual causes: high-mileage ash loading; oil consumption; wrong engine oil

Mazda

Mazda meaning: DPF soot load has passed the acceptable limit (over 17 g/l on SkyActiv-D 1.5). Past normal regen; price a DPF replacement or professional clean.

Usual causes: DPF blocked beyond regeneration; pipe to exhaust gas pressure sensor No.2 restricted or damaged; pressure sensor connector fault

Mitsubishi

DPF restricted by ash. Ash does not burn off; regeneration can no longer clear the filter.

Usual causes: DPF at end of life (ash full) after high kms or many regens; oil consumption adding ash; repeated failed regenerations

Nissan

DPF ash build-up too high: regeneration can no longer clear the filter (Navara D23/NP300).

Usual causes: DPF full of ash or soot (high km, short trips); wrong or overdue engine oil; failed regenerations (e.g. faulty glow plugs)

Skoda

DPF restricted or clogged with ash. Usually needs a DPF clean or replacement, and correct ECU software for the DPF fitted.

Usual causes: ash-loaded / clogged DPF; failed DPF; wrong ECU software for the DPF type (e.g. Crafter)

Volkswagen

DPF restricted or clogged with ash. Usually needs a DPF clean or replacement, and correct ECU software for the DPF fitted.

Usual causes: ash-loaded / clogged DPF; failed DPF; wrong ECU software for the DPF type (e.g. Crafter)

Volvo

DPF restriction from ash. Filter needs cleaning or replacing.

Usual causes: high-mileage ash loading; oil consumption; wrong engine oil

What the repair usually costs

CVT valve body replacement (remanufactured, in car)NZ$1,280–NZ$2,420 · A$1,200–A$2,400
PCV valve / oil separator replacementNZ$110–NZ$920 · A$110–A$900
DPF off-car clean (sent out)NZ$740–NZ$1,890 · A$740–A$1,820
DPF replacement (diesel ute / SUV)NZ$1,790–NZ$8,460 · A$1,330–A$6,800

Not sure what P242F means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.