DTC P0442 Or P0455: Condition

DTC P0442 is set when fuel tank pressure increases more than specified value, a small leak in EVAP system is detected.

DTC P0455 is set when fuel tank pressure change is less than specified value, a large leak in EVAP system is detected. MIL is illuminated when ECM detects malfunction during 2 consecutive drive cycles. Possible causes are:

• ECM malfunction.
• EVAP canister.
• EVAP canister control valve.
• EVAP control system circuits malfunction.
• EVAP control system vacuum hoses malfunction.
• Fuel level sensor malfunction.
• Fuel tank component malfunction.
• Fuel Tank Pressure (FTP) sensor malfunction.
• Leaking fuel pump assembly seal on fuel tank.
• Missing, loose or malfunctioning fuel filler cap, or leak from cap gasket.