On the 2006 Pontiac Montana, the P0449 is a fairly straight forward code pointing to a problem with the EVAP Vent Solenoid Valve. On this vehicle, the Vent Valve is located on top of the fuel tank, mounted next to the EVAP Canister. To gain access, the fuel tank will need to be dropped. Carefully inspect the rubber and plastic lines to/from the vent valve and canister for any cracks, holes or disconnections. Inspect the electrical connector and wire harness to the vent valve for any loose, broken or damaged wires. If no problems are found, replacing the EVAP Vent Solenoid Valve should solve this issue. To replace- drop the fuel tank. Disconnect the electrical connector. Remove the hose from the vent valve. Release the locking tab and removed the vent valve from the bracket.
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