P1449 Buick Evaporative Check Solenoid Circuit Malfunction

P1450 Buick Unable To Bleed Up Fuel Tank Vacuum

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.
    • Symptoms
    – Engine Light ON (or Service Engine Soon Warning Light)
    P1450 Buick 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).

    Buick Vehicle:Buick Regal – ?Buick Riviera – ?Buick LaCrosse – ?David Dunbar Buick – Buick Century – Buick LaCrosse – Buick LeSabre – Buick Lucerne – Buick Park Avenue – Buick Regal – Buick Verano – Buick Enclave – Buick Encore – Buick Rainier – Buick Rendezvous – Buick Terraza – Buick Riviera