2007 Nissan Sentra Q&A
2007 Nissan Sentra Question: What to check for a OBD II P0456 Code? I replaced the gas cap and no help!
use a smoke machine and watch for smoke exiting the system at any EVAP component. Any where there is smoke exiting the system, that is the faulty component. Do not pressurize the EVAP system with air pressure. Doing so can damage the purge and vent solenoids in the system. - chinasinoy