DTC 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. This DTC sets 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 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 EVAP canister vent valve stuck partially or fully closed Plugged EVAP canister vent valve filter EVAP purge valve stuck open VREF circuit open Damaged FTP sensor
Diagnostic Aids: Visually inspect the EVAP canister inlet port, EVAP canister vent valve filter, and EVAP canister vent hose assembly for contamination or debris. Check EVAP purge valve for vacuum leak.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST HX .