Possible Causes

WARNING: This page is about a different car, the 2002 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

Malfunction is detected when EVAP control system does not operate properly, or there is a leak between intake manifold and EVAP-CSPS. Possible causes are:

EVAP-CPVCSV stuck closed.
Faulty EVAP-CSPS or circuit.
Loose, disconnected or improper connection of hoses.
Blockage in hoses.
Cracked EVAP canister.
Faulty EVAP-CPVCSV circuit.
Defective Accelerator Pedal Position (APP) sensor.
Blocked purge port.
Defective EVAP Canister Vent Control Valve (EVAP-CVCV).