What does it mean?
P1405 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: DPFE Sensor Upstream Hose Off Or Plugged .
Symptoms
- MIL on
- Rough idle and stumbling right off idle
- Hesitation during light acceleration
- Mild surging at a steady speed
- Higher fuel consumption and an emissions test failure
- A faint hiss or ticking from a loose hose in some cases
Likely causes
- Upstream hose fallen off, split or cracked at the sensor or the EGR tube fitting
- Hose plugged with soot or carbon deposits
- Rubber hose hardened and broken by exhaust heat
- Hoses swapped during a previous repair
- Restricted EGR tube or metering orifice upstream of the sensor
- Failed DPFE sensor reporting an implausible value
- Corroded connector affecting the signal
How to fix it
- Inspect both DPFE hoses at the sensor and at the EGR tube: confirm they are attached, intact and correctly routed
- Remove the upstream hose and blow through it to confirm it is clear
- Check the tube fitting for soot build-up and clean the passage
- Replace heat hardened rubber hoses with the correct heat resistant type
- Compare the DPFE voltage at rest with the specification
- Clean the EGR tube and metering orifice if restricted
- Replace the DPFE sensor only after the hoses and passages are proven clear, then verify EGR flow in live data