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 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, EVAP the canister purge valve and the EVAP canister). Fuel filler cap stuck closed (no vacuum relief). Contaminated fuel vapor elbow on the EVAP canister. Restricted EVAP canister. CV solenoid stuck open (partially or fully). Plugged CV solenoid filter. EVAP canister purge valve stuck open. VREF circuit open (harness near FTP sensor, FTP sensor or PCM). Damaged FTP sensor.
Diagnostic Aids:	-
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	-	-	GO to HX: Evaporative Emission (EVAP) Monitor and System STEP 9