P244B Diesel Particulate Filter Differential Pressure Too High (Bank 1)
P244B is a generic OBD2 powertrain code. It means “Diesel Particulate Filter Differential Pressure Too High (Bank 1)” — the same on every make and model, because the definition comes from the SAE J2012 standard rather than from the carmaker.
Ask the AI about P244B on your car- System
- Powertrain (P)
- Code type
- Generic (SAE)
- Range
- P24xx
- Urgency
- High
What P244B means
The diesel particulate filter has collected more soot than it should (P2463), or the pressure difference across it is too high (P244B): the filter isn’t burning itself clean — regenerating — the way it should.
Symptoms
- A DPF warning lamp
- Loss of power or limp mode
- Frequent regeneration attempts — a raised idle, fans running after switch-off, a hot smell
Most likely causes
- Mostly short trips that never give the filter a chance to regenerate
- Regenerations interrupted before they finish
- The wrong engine oil (not low-ash) or high oil consumption
- A faulty differential-pressure sensor
- An injector, EGR or turbo fault producing extra soot
What to check first
- If your car allows it, drive 20–30 minutes at a steady highway speed to trigger a regeneration
- Check the pressure sensor and its hoses
- Ask a workshop for a forced regeneration before anyone quotes a new filter
- Fix any EGR, injector or boost codes stored alongside
Can I keep driving with P244B?
Limit driving — get it checked promptly
Only to clear it, or to the workshop. A badly overloaded filter can’t be regenerated safely and may have to be replaced — and the longer you drive on it, the likelier that becomes.
What the wording tells you
The wording describes a quantity — a pressure, a speed, a voltage, a temperature — that measured higher than it should. The circuit is usually fine: the system itself is out of range, so check the mechanical or hydraulic side (and the sensor’s accuracy) before the wiring.
Bank 1: engines with two rows of cylinders — V6, V8, boxer — have two banks. Bank 1 is the side that holds cylinder 1, bank 2 the other side; an inline engine has only bank 1.
How P244B breaks down
Powertrain. Engine, transmission, fuel and emissions — the codes behind the check engine lamp.
Generic code: defined by SAE, the same on every make.
Auxiliary emission controls.
The specific fault within this range.
Where to look: Auxiliary emission controls
The systems that clean up exhaust and fuel vapor: exhaust gas recirculation (EGR), secondary air injection, catalytic converter monitoring, the evaporative emissions (EVAP) system with its purge and vent valves — plus exhaust temperature sensors, the particulate filter and some cooling-fan circuits.
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Frequently asked
What does P244B mean?
P244B is a generic OBD2 powertrain code. It means “Diesel Particulate Filter Differential Pressure Too High (Bank 1)” — the same on every make and model, because the definition comes from the SAE J2012 standard rather than from the carmaker. The diesel particulate filter has collected more soot than it should (P2463), or the pressure difference across it is too high (P244B): the filter isn’t burning itself clean — regenerating — the way it should.
Can I drive with P244B?
Only to clear it, or to the workshop. A badly overloaded filter can’t be regenerated safely and may have to be replaced — and the longer you drive on it, the likelier that becomes.
What causes P244B?
Mostly short trips that never give the filter a chance to regenerate; Regenerations interrupted before they finish; The wrong engine oil (not low-ash) or high oil consumption; A faulty differential-pressure sensor; An injector, EGR or turbo fault producing extra soot.
How do I clear P244B?
Fix the cause first, then clear it with any OBD2 scanner or app. Once the fault is gone the car also clears it on its own: the check engine lamp goes off after the self-test passes on three drive cycles in a row, and the stored code ages out after about 40 warm-ups. Clearing without a repair only hides it for a while — and resets the readiness monitors an emissions inspection looks at.
Is P244B the same on every car?
Yes. P244B is a generic SAE J2012 code, so its definition is identical on every make and model. What differs is the cause behind it and the repair procedure, which depend on the engine — that’s why the assistant on this page asks for your car.
Guides
Definitions: the generic SAE J2012 codes from Brimly’s offline dictionary (data version 2026.09). Causes and advice are general guidance for all makes — the service information for your car has the last word.