OBD-II · Engine and powertrain (P)
P244A
DPF differential pressure too low bank 1
What it means
The measured pressure difference across the bank 1 DPF is lower than expected for the exhaust flow. Possible explanations include pressure-sensor or hose faults, exhaust leaks, or a damaged or missing filter substrate.
Symptoms
- engine warning light
- sometimes reduced power (limp mode)
- possibly soot at the tailpipe if the filter is cracked
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | disconnected, split or blocked pressure sensor hose |
| 02 | faulty differential pressure sensor |
| 03 | exhaust leak before the DPF |
| 04 | cracked or melted DPF substrate |
| 05 | DPF removed or hollowed out (illegal for road use in most of Europe) |
What to check, step by step
- 01Inspect both sensor hoses end to end, including the metal pipes at the exhaust, for splits and blockage.
- 02Compare live differential pressure at idle and at raised rpm against expected values.
- 03Check for exhaust leaks before the DPF.
- 04Look for fresh soot after the DPF (cracked filter).
- 05Replace the sensor only when hoses and exhaust are proven good.