Audi P242F

DPF ash mass limit on Audi TDI — 2.0/3.0 TDI end-of-life DPF, more common on Sportback/estate short-run cars.

Audi P242F — DPF ash mass limit on Audi TDI — 2.0/3.0 TDI end-of-life DPF, more common on Sportback/estate short-run cars. Typical UK independent garage cost: £850–£2500.

What actually causes P242F on a Audi

A6 C7 3.0 TDI: DPF ash issues common on cars used for short trips and school runs — dieselgate updates made this worse. A3/A4 EA189 hits P242F around 110–140k miles.

Audi engines that log P242F

• 2.0 TDI EA189 (A3, A4 B8, A6 C7)
• 2.0 TDI EA288 (A3 8V, A4 B9)
• 3.0 TDI CR (A6, A7, Q5, Q7)

How we diagnose P242F on a Audi

1. VCDS block 75 — ash mass and regen count
2. 3.0 TDI CR — pressure-test EGR cooler first
3. Off-vehicle ultrasonic clean where cell integrity holds
4. OE Audi DPF, ODIS ash mass adaptation reset

The common misdiagnosis to avoid

3.0 TDI CR — replacing the DPF without inspecting the EGR cooler is money wasted. Cracked cooler will contaminate a new DPF within months.

Audi P242F repair cost in the UK

Expect £850–£2500 including parts and labour at an independent garage. Main-dealer quotes on Audi are usually higher for the same job, and the spread exists because the cheap cause and the expensive cause throw the same code — pay for the diagnosis before you pay for parts.

Bob's workshop tip

A6 3.0 TDI — pressure-test the EGR cooler before spending on a DPF. Fix upstream causes.

Codes usually seen alongside P242F on Audi

• P2002
• P244A
• P042F

Symptoms drivers report with P242F

• DPF warning light on the dash steady (not flashing) — often accompanied by 'Engine System Fault, Service Now'
• Reduced Engine Power warning / limp mode after another attempted regen
• Car has done multiple 'passive regens' recently (higher revs at motorway cruise, warm smell like burning) that ended incomplete
• MPG dropped 5–12 mpg over recent months as the DPF partially blocked
• Slight loss of turbo response and top-end power, engine feels 'flat'
• Exhaust smells 'hot' or 'sulphurous' after a long drive — sign of forced-regen attempts

Repairs that clear P242F

• Replace or professionally clean DPF

For the generic, all-makes explanation of this code — meaning, every known cause and UK cost bands — see our P242F guide.

Reading P242F on a Audi properly

A generic reader will show P242F and nothing else. What matters is the freeze-frame data stored with it — engine speed, load, coolant temperature and fuel trims at the moment the fault was logged — plus whether any other module on the Audi has logged something at the same time. Codes rarely arrive alone, and the order they were stored in usually points at which one is the cause and which are the consequences.

Clearing P242F without fixing it

Erasing the code resets the Audi's readiness monitors as well as the light. The fault returns on the next drive cycle if the cause is still there, and in the meantime the incomplete monitors can stop the car passing an emissions check. After a genuine repair, the car is driven until the relevant monitor completes before it is handed back.

Bob's Mechanical Repairs is an independent garage in Birnam, Dunkeld, Perthshire, with 32 years of Bob's experience on the tools. If P242F is showing on your Audi, bring any scan results with you — we will read the live data ourselves, confirm which cause it actually is, and price the repair before any work starts.