What does it mean?
P1452 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Differential Pressure Sensor Hose Performance .
Symptoms
- MIL on with related pressure or flow codes stored at the same time
- Sensor value stuck near zero or implausibly high in live data
- On diesel applications, filter regeneration may not start or may run too often
- Slight power loss and increased fuel consumption when regeneration control is disturbed
- No unusual noises, so the fault is easy to overlook without a scan tool
Likely causes
- Cracked, split or perished sensor hose, often hardened by exhaust heat
- Hose blocked by soot, condensate or ash, common on diesel particulate filter applications
- Kinked or crushed hose after service work or from contact with a hot component
- Hose disconnected or fitted to the wrong port, reversing the reading
- Water trapped in the hose freezing in cold weather
- Corroded or blocked take off fittings at the exhaust or intake connection
- Sensor port itself plugged with debris
How to fix it
- Read the differential pressure value with the engine off; it should be close to zero
- Remove both ends of the hose and blow through it to confirm it is clear along its whole length
- Inspect the hose for cracks, hardening, kinks and heat damage, replacing it if in doubt
- Check the take off fittings on the exhaust or intake for soot blockage and clean them
- Confirm the hoses are on the correct ports and not reversed
- Watch the sensor value while gently applying pressure with a hand pump to see whether it responds smoothly
- Replace the hose or the sensor as needed, then clear the code and verify the reading at idle and under load