P1450 - Unable to Bleed Up Fuel Tank Vacuum
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 the fuel tank pressure [FTP] sensor, the FTP sensor or the powertrain control module [PCM])
- Damaged FTP sensor
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.