DTC P1454: Fuel Tank Pressure (FTP) Sensor Range/Performance Problem: General Description

The fuel tank pressure is about 0 kPa (0 inHg, 0 mmHg) when starting a cold engine. When the fuel tank pressure (FTP) sensor output value is out of a specified range and the powertrain control module (PCM) judges that there's no other cause [no evaporative emission (EVAP) canister vent shut valve failure, etc.] for the FTP sensor zero point shift, the PCM detects an FTP sensor malfunction. However, if the FTP sensor output when starting the engine, is a prescribed negative value or less (excessive negative pressure is detected), the malfunction judgment should be done as follows because it is difficult to distinguish the FTP sensor zero point shift (P1454) from the EVAP canister vent shut valve failure (P2422).

1. If neither Pending DTCs (P1454 nor P2422) are stored, both Pending DTCs are stored when excessive vacuum is detected at engine start.
2. If both Pending DTCs (P1454 and P2422) are stored and excessive vacuum is detected, both Confirmed DTCs are stored.
3. If either Pending DTC (P1454 or P2422) is stored and excessive vacuum is detected, the PCM stores the Confirmed DTC which the Pending DTC is stored.