P0455 Evaporative Emission System Leak Detected (Gross Leak)
The fuel tank may be under a slight positive and negative pressure depending on the state of the evaporative emission system. The PCM monitors and responds to these pressure changes. If the pressure varies from the specified range, the PCM will set DTC P0455.
The PCM energizes the evaporative emission ventilation solenoid to shut off the evaporative emission canister outlet port.
The evaporative emission purge solenoid is to apply engine manifold vacuum to the evaporative emission system.
When the fuel system develops a vacuum of 2 kPa (0.29 psi), the evaporative emission purge solenoid is turned "OFF" and the fuel system vacuum is maintained at 2 kPa (0.29 psi).
The PCM determines if there is a leak or clog in the fuel system by measuring the change of vacuum inside the fuel tank.
The test is stopped when fuel vapor pressure is determined to be too high.
DTC SET CONDITIONS
Test Conditions:
Engine coolant temperature is less than 36°C (97°F) when the engine is started.
Intake air temperature is less than 36°C (97°F) when the engine is started.
Engine coolant temperature is greater than 60°C (140°F) When the amount of remaining fuel is 15 − 40 percent of capacity upon engine start up.
Engine coolant temperature is greater than 20°C (68°F) when the amount of remaining fuel is 40 − 85 percent of capacity upon engine start up.
Intake air temperature is greater than 5°C (41°F).
Fuel tank temperature is less than 36°C (97°F).
Barometric pressure is greater than 76 kPa (11 psi).
Volumetric efficiency is between 20 and 70 percent.
Fuel tank differential pressure sensor output voltage is 1 − 4 volts.
When the evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure in the fuel tank rises to 451
Pa (0.065 psi) or less and the amount of remaining fuel is 15 − 40 percent of capacity upon engine start up.
When the evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure in the fuel tank rises to 324 Pa (0.047 psi) or less and the amount of remaining fuel is 40 − 85 percent of capacity upon engine start up.
Engine speed is greater than 1,600 r/min.
10 seconds have elapsed from the start of the previous monitoring.
Monitoring time: 150 seconds.
Judgment Criteria:
The fuel tank internal pressure is greater than 2 kPa (0.29 psi) after the evaporative emission purge solenoid has been driven when the fuel tank and vapor line were closed.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Loose fuel cap.
- Fuel cap relief pressure is incorrect.
- Malfunction of the fuel overflow limiter valve.
- Purge line or vapor line is clogged.
- Malfunction of the fuel tank, purge line or vapor line seal.
- Malfunction of the evaporative emission purge solenoid.
- Malfunction of the evaporative emission ventilation solenoid.
- Malfunction of the fuel tank differential pressure sensor.
- Malfunction of the evaporative emission canister seal.
- Evaporative emission canister is clogged.
-
OVERVIEW OF TROUBLESHOOTING
To determine the cause of DTC P0455, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool MB991502 set to data reading mode for the fuel tank differential pressure sensor (TANK PRES SNER 73). The mechanical gauge reading is used to verify the scan tool reading. A comparison of the mechanical gauge and scan tool MB991502 determines whether there is a problem in the system
Prior to doing the performance test, ensure that the fuel cap is closed securely. Inspect all EVAP system hoses and tubes for damage.
The fuel tank may be under a slight positive and negative pressure depending on the state of the evaporative emission system. The PCM monitors and responds to these pressure changes. If the pressure varies from the specified range, the PCM will set DTC P0455.
The PCM energizes the evaporative emission ventilation solenoid to shut off the evaporative emission canister outlet port.
The evaporative emission purge solenoid is to apply engine manifold vacuum to the evaporative emission system.
When the fuel system develops a vacuum of 2 kPa (0.29 psi), the evaporative emission purge solenoid is turned "OFF" and the fuel system vacuum is maintained at 2 kPa (0.29 psi).
The PCM determines if there is a leak or clog in the fuel system by measuring the change of vacuum inside the fuel tank.
The test is stopped when fuel vapor pressure is determined to be too high.
DTC SET CONDITIONS
Test Conditions:
Engine coolant temperature is less than 36°C (97°F) when the engine is started.
Intake air temperature is less than 36°C (97°F) when the engine is started.
Engine coolant temperature is greater than 60°C (140°F) When the amount of remaining fuel is 15 − 40 percent of capacity upon engine start up.
Engine coolant temperature is greater than 20°C (68°F) when the amount of remaining fuel is 40 − 85 percent of capacity upon engine start up.
Intake air temperature is greater than 5°C (41°F).
Fuel tank temperature is less than 36°C (97°F).
Barometric pressure is greater than 76 kPa (11 psi).
Volumetric efficiency is between 20 and 70 percent.
Fuel tank differential pressure sensor output voltage is 1 − 4 volts.
When the evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure in the fuel tank rises to 451
Pa (0.065 psi) or less and the amount of remaining fuel is 15 − 40 percent of capacity upon engine start up.
When the evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure in the fuel tank rises to 324 Pa (0.047 psi) or less and the amount of remaining fuel is 40 − 85 percent of capacity upon engine start up.
Engine speed is greater than 1,600 r/min.
10 seconds have elapsed from the start of the previous monitoring.
Monitoring time: 150 seconds.
Judgment Criteria:
The fuel tank internal pressure is greater than 2 kPa (0.29 psi) after the evaporative emission purge solenoid has been driven when the fuel tank and vapor line were closed.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Loose fuel cap.
- Fuel cap relief pressure is incorrect.
- Malfunction of the fuel overflow limiter valve.
- Purge line or vapor line is clogged.
- Malfunction of the fuel tank, purge line or vapor line seal.
- Malfunction of the evaporative emission purge solenoid.
- Malfunction of the evaporative emission ventilation solenoid.
- Malfunction of the fuel tank differential pressure sensor.
- Malfunction of the evaporative emission canister seal.
- Evaporative emission canister is clogged.
-
OVERVIEW OF TROUBLESHOOTING
To determine the cause of DTC P0455, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool MB991502 set to data reading mode for the fuel tank differential pressure sensor (TANK PRES SNER 73). The mechanical gauge reading is used to verify the scan tool reading. A comparison of the mechanical gauge and scan tool MB991502 determines whether there is a problem in the system
Prior to doing the performance test, ensure that the fuel cap is closed securely. Inspect all EVAP system hoses and tubes for damage.