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This code typically sets when there is a problem in the evap vent solenoid valve. This solenoid controls venting of the fuel vapors in the tank, so the tank may be holding pressure or a vacuum. Replacing the vent valve is the fix for this problem. The vent valve is located near the charcoal canister on the drivers side of the vehicle, underneath near the front of the fuel tank.
The fuel tank does not need to be removed. The vent solenoid is located on the frame crossmember near the front of the tank. See picture.