P244A
Diesel Particulate Filter Differential Pressure Too LowP244A is a generic OBD-II powertrain diagnostic trouble code: Diesel Particulate Filter Differential Pressure Too Low. It is logged by the engine control unit when the dpf monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.
What P244A means
P244A is a generic SAE powertrain diagnostic trouble code that sets when the engine control module detects that the differential pressure across the diesel particulate filter (DPF) is lower than the expected calibrated range. The DPF differential pressure sensor compares exhaust pressure upstream and downstream of the filter; the ECM uses this delta to estimate soot loading and to schedule regeneration cycles. When the reading stays below the expected threshold under conditions where some restriction should be present, the ECM concludes that the signal is implausible or that exhaust is bypassing the filter element.
Although P244A on its own is not an immediate driveability emergency, it does indicate that the aftertreatment system can no longer reliably manage soot loading. Vehicles may continue to run normally at first, but the ECM will typically illuminate the malfunction indicator lamp and may inhibit active regeneration. If the underlying cause is a cracked or hollowed-out DPF substrate, an exhaust leak between the sensor ports, or a disconnected pressure line, the vehicle is also emitting more particulate matter than the design allows.
The code is most commonly seen on European diesels (Mercedes-Benz, BMW, VAG group, Ford, PSA) and light-duty diesel trucks. Diagnosis should focus on the pressure sensor, its hoses, and the physical integrity of the DPF and exhaust before any component is replaced.
Common causes
Most-frequently reported root causes when P244A is logged.
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1
Faulty or drifting DPF differential pressure sensor.
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2
Disconnected, cracked, clogged, or swapped pressure sensor hoses between the sensor and the DPF tap points.
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3
Exhaust leak upstream of the DPF or between the two pressure measurement ports.
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4
Damaged or hollowed-out DPF substrate allowing exhaust to bypass the filter element.
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5
Wiring or connector faults in the differential pressure sensor circuit.
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6
Previous DPF removal or tampering that leaves the sensor reading unrealistic values.
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7
ECM software calibration issue or outdated control module firmware.
Symptoms drivers notice
How to diagnose P244A
A typical diagnostic flow when this code is present.
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1
Scan the vehicle for all stored and pending DTCs and record freeze frame data alongside P244A.
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2
Monitor live differential pressure sensor data at idle and under load, comparing against expected values for the engine.
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3
Visually inspect the differential pressure sensor, its electrical connector, and both pressure hoses for cracks, soot blockage, or disconnection.
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4
Inspect the exhaust system from the turbo outlet through the DPF for leaks, loose clamps, and damaged gaskets.
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5
Test the differential pressure sensor signal against a known reference (for example, by briefly disconnecting one hose) to confirm the sensor responds.
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6
If sensor and plumbing are good, inspect the DPF itself for substrate damage, melting, or evidence of prior removal.
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7
Clear the code, perform a road test or commanded regeneration, and verify that the differential pressure trace returns to the expected range.
Vehicles where we've handled P244A
Platforms in our catalogue with confirmed P244A coverage.
Related powertrain codes
- P2002 — Diesel Particulate Filter Efficiency Below Threshold Bank 1
- P2003 — Diesel Particulate Filter Efficiency Below Threshold Bank 2
- P200C — Diesel Particulate Filter Over Temperature Bank 1
- P200D — Diesel Particulate Filter Over Temperature Bank 2
- P200E — Catalyst System Over Temperature Bank 1
- P226D — Particulate Filter Deteriorated / Missing Substrate Bank 1
Frequently asked questions
Is it safe to drive with a P244A code?
Short trips to a workshop are generally safe, but the vehicle may enter limp mode and regeneration is usually inhibited, so the issue should be diagnosed promptly to avoid further DPF or emissions damage.
Does P244A always mean the DPF is bad?
No. In many cases the DPF itself is fine and the fault lies with the differential pressure sensor, its hoses, or an exhaust leak. The filter should only be condemned after sensor and plumbing checks rule out cheaper causes.
Can a clogged DPF cause P244A?
A heavily clogged DPF normally raises differential pressure rather than lowering it, so it typically sets pressure-too-high codes. However, a DPF whose substrate has cracked or melted internally can produce abnormally low pressure and trigger P244A.
Will the code clear itself after a regeneration?
If the root cause was a transient sensor reading or a temporarily blocked hose, the code may self-clear after several successful drive cycles. A persistent or recurring P244A indicates a real fault that will not resolve without repair.
Disabling P244A in software
RaceTune can permanently disable P244A — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.
ECUs with a P244A disable in our catalogue
Confirmed coverage from our recipe database — we support many more families. Upload your file and our identifier will match it automatically.
- Bosch EDC17C50 verified 1 software version
- Bosch EDC17CP09 verified 1 software version
Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.
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