P0455

Evaporative Emission System Monitoring - 0.020" (0.5mm) Diameter











Evaporative Emission System Monitoring - 0.040" (1.0mm) Diameter











DTC P0455
Evaporative control system - large leak detected Drive cycle C:Signal out of range - below minimum.

Possible causes by suggested order of priority:
- Fuel filler cap missing.
- Disconnected hose.
- Disconnected fuel tank pressure sensor.
- Clogged hose.
- Clogged fuel tank pressure sensor line.
- Faulty Purge valve - does not open.
- Fuel tank pressure sensor fault.

Fuel filler cap missing.
CHECK THE FOLLOWING:
- Check fuel filler cap is fitted correctly and not leaking.
POSSIBLE FAULTS
- Faulty or missing fuel filler cap.
Disconnected hose.
CHECK THE FOLLOWING:
- Check all hose connections in evaporative loss system:
- Hoses in fuel tank filler assembly.
- Hoses connecting fuel tank filler assembly to purge cannister.
POSSIBLE FAULTS
- Faulty hose or hose connection.

Disconnected fuel tank pressure sensor.
CHECK THE FOLLOWING:
- Visual check of the pipe connecting fuel tank pressure sensor to fuel tank
- Monitor fuel tank pressure reading on real time data and rock vehicle to cause fuel slosh. Pressure reading should vary (Fuel tank must be nearly full).
POSSIBLE FAULTS
- Fuel tank pressure sensor pipe disconnected.

Clogged hose.
CHECK THE FOLLOWING:
- Hose connecting fuel tank filler assembly to purge cannister not blocked.
POSSIBLE FAULTS
- Clogged hose between Fuel tank and purge cannister.

Clogged fuel tank pressure sensor line.
CHECK THE FOLLOWING:
- Disconnect pipe connecting fuel tank pressure sensor to fuel tank, attempt to blow through pipe.
- Monitor fuel tank pressure reading on real time data and rock vehicle to cause fuel slosh. Pressure reading should vary (Fuel tank must be nearly full).
POSSIBLE FAULTS
- Fuel tank pressure sensor pipe blocked.
Faulty Purge valve - does not open.
CHECK THE FOLLOWING:
- Visual check of purge valve for blockage or damage.
- Check purge valve by substituting a known good unit.
POSSIBLE FAULTS
- Purge valve blocked or jammed.

Fuel tank pressure sensor fault.
CHECK THE FOLLOWING:
- Pressure sensor reads close to zero with filler cap removed.
- If equipment available pressurize the tank and check that the reading on the sensor is accurate.
POSSIBLE FAULTS
- Faulty fuel tank pressure sensor.