P2452 / P2453 — DPF Pressure Sensor Performance
The ECU distrusts the differential-pressure sensor's signal — stuck, implausible or out of range. These are sensor-circuit codes: the DPF itself may be perfectly healthy.
What commonly causes it
- ·Failed differential-pressure sensor (very common on high-mileage diesels)
- ·Cracked, melted or soot-blocked sensor hoses — a known weak point on GM/Vauxhall CDTi units
- ·Corroded connector or wiring chafe near the bulkhead
- ·Water ingress into the sensor after engine-bay cleaning
Test this before blaming the DPF
- ·Read the sensor's live value with the engine off — a non-zero static reading means sensor or hose, not filter
- ·Inspect and blow through both sensor pipes (they block with soot on GM units)
- ·Check connector pins and wiring before replacing anything
Will cleaning fix it?
Usually not — these are sensor codes, not blockage codes. Fit the sensor/hoses first. Where a genuinely loaded filter caused the sensor to soot up internally, we'll see it on inspection and advise cleaning as well.
Engines this disproportionately affects
Check your vehicle & get a quote
Enter your registration — we'll identify the exact unit and give you the correct recommendation for this fault.
Vehicle data from the DVSA MOT history service. We confirm the exact unit on inspection. Privacy
Test evidence
Every unit is flow- and pressure-tested before and after cleaning. You get the readings, photo evidence and a completion certificate with the unit — proof for you and your customer, not marketing numbers.