P0455

Condition
The EVAP canister shut-off valve is closed, this means that the fuel tank system is closed. The Canister purge (CP) valve is pulsed, pressure in the fuel tank should drop rapidly. Diagnostic trouble code (DTC) ECM-4038 is stored if the pressure in the fuel tank does not drop rapidly enough. This diagnostic trouble code (DTC) is stored in the first operating cycle that the fault is discovered, in order to warn the driver with a text message that the fuel tank filler cap might be loose or not installed. ECM-4308 Fuel tank system large leak is stored at the same time.

Substitute value
None.

Possible source
Major leak.

Fault symptom[s]
None.

Condition







When the EVAP canister shut-off valve is closed the fuel tank system should be sealed. When the evaporative emission system (EVAP) valve is activated the fuel tank pressure must fall to a set negative pressure or it will be interpreted as a major leak. Then the evaporative emission system (EVAP) valve closes. The fuel tank pressure must not rise too quickly, this is interpreted as a minor leak. Diagnostic trouble code (DTC) ECM-4308 is stored if the control module registers a minor or major leak.

Substitute value
None.

Possible source

Major leak:
- Leaking fuel tank, filler pipe, fuel tank filler cap, evaporative emission system (EVAP) canister, evaporative emission system (EVAP) canister shut-off valve or lines between these components
- Blocked evaporative emission system (EVAP) valve
- Blocked hoses to the fuel tank pressure sensor or defective fuel tank pressure sensor. Does not react to changes in pressure.

Minor leak:
- Leaking fuel tank, fuel filler pipe, fuel tank filler cap, EVAP canister, canister purge (CP) valve, or in the hoses between these components.

Fault symptom[s]
None.