The Quick Answer above is the generic definition. What follows is the model-specific detail for the BMW models that log P244B.
DTC/P244B·BMW
P244B on BMW: Causes, Symptoms and Fix Cost
Quick Answer
High SeveritySafe to drive (short-term)BMW
P244B on a BMW means the differential pressure across the diesel particulate filter is higher than the ECU expects, indicating the filter is heavily loaded with soot. The usual cause is a DPF that has failed to complete its passive regeneration cycle because the vehicle is driven mostly on short urban trips. Less commonly, the pressure sensor itself is reading high, the DPF substrate has melted or cracked internally, or there is a downstream exhaust restriction.
Typical repair cost, all makes€60 - €3600
Connect any standard Bluetooth OBD2 adapter to your BMW and Skanyx tells you what P244B means on that engine, whether it is safe to keep driving, and what the fix should cost. Free on iPhone and Android.
Get Skanyx freeWhat does P244B mean on a BMW?
BMW 3 Series Diesel
2009-2024BMW diesels with the N47, N57 and B47 engines are sensitive to short-trip duty cycles. A BMW used as a daily commuter for short journeys is a typical P244B candidate, because the filter rarely gets hot enough to regenerate on its own. Cleaning the existing filter off the car costs far less than a new one.
What causes P244B on a BMW?
Beyond the generic causes listed on the main P244B page, these are the patterns noted for BMW models:
BMW 3 Series DieselShort urban duty cycle on commuter N47/B47
BMW 3 Series DieselInterrupted regeneration cycles (driver shuts engine off mid-regen)
How to diagnose P244B on a BMW with OBD2
Follow these steps to pinpoint the root cause of P244B:
- With manufacturer-level software, read the DPF soot mass, distance since the last regeneration, the count of completed regenerations and the current differential pressure (a generic OBD2 reader cannot show these on most cars). A high soot mass with no recent regeneration points to an overloaded filter; the threshold that counts is the one for that vehicle, not a universal figure
- Before any parts replacement, have a forced regeneration run with manufacturer-level software (a generic OBD2 reader cannot trigger one). A successful forced regen brings the calculated soot mass back down below the threshold for that vehicle and can resolve P244B without further repair, especially on a vehicle that has been driven on short trips
- If forced regeneration fails or the soot mass refuses to drop, the DPF is either physically damaged or so loaded that off-vehicle cleaning is needed. Off-vehicle cleaning usually takes 1 to 2 days at a specialist and costs far less than a new filter
- With manufacturer-level software, compare the differential pressure reading to the manufacturer specification at idle and under load. A reading that is high at idle but normal under load points to a faulty sensor rather than a clogged filter. The sensor is far cheaper to replace than the DPF
- Inspect the DPF substrate with a borescope through the inlet flange. A cracked or melted substrate is visible and cannot be cleaned, only replaced. Catastrophic regeneration events (often after a misfire or rich condition) destroy the substrate
- Confirm there is no downstream restriction by checking the exhaust system from DPF outlet to tailpipe. A collapsed muffler or crushed pipe section will mimic a clogged DPF
How much does P244B cost to fix on a BMW? (EUR)
Estimated repair costs for P244B in EUR, compiled across makes. Expect BMW parts and labour towards the upper end of each range.
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
Codes related to P244B
These codes are often seen alongside P244B or point to related issues, on any make:
Looking for the full P244B reference (all makes, full diagnosis flow, complete repair cost matrix)?
See the main P244B guideSkanyx · BMW
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