P1450 - Unable To Bleed Up Fuel Tank Vacuum

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P1450 - UNABLE TO BLEED UP FUEL TANK VACUUM

Description:	Monitors the fuel vapor vacuum and pressure in the fuel tank. System failure occurs when the evaporative emission (EVAP) running loss monitor detects excessive fuel tank vacuum with the engine running, but not at idle.
Possible Causes:	Blockages or kinks in the EVAP canister tube or EVAP canister purge outlet tube between the fuel tank, the EVAP canister purge valve and the EVAP canister Fuel filler cap stuck closed, preventing vacuum relief Capless fuel tank filler pipe damaged, preventing vacuum relief (if equipped) Contaminated fuel vapor elbow on the EVAP canister Restricted EVAP canister CV solenoid stuck partially or fully open Plugged CV solenoid filter EVAP canister purge valve stuck open VREF circuit open in the harness near the fuel tank pressure (FTP) sensor, the FTP sensor or the powertrain control module (PCM) Damaged FTP sensor
Diagnostic Aids:	Visually inspect the EVAP canister inlet port, CV solenoid filter, and canister vent hose assembly for contamination or debris. Check EVAP canister purge valve for vacuum leak.
Application		Key On Engine Off	Key On Engine Running	Continuous Memory
All		-	-	refer to PINPOINT TEST HX .