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TECHNICAL DESCRIPTION
• The PCM monitors the Evaporative Emission (EVAP) System pressure.
• The PCM controls the evaporative emission ventilation solenoid. It closes the evaporative emission ventilation solenoid to seal the evaporative emission canister side of the system.
• The evaporative emission purge solenoid is opened to allow manifold vacuum to create low pressure (vacuum) in the EVAP system.
• When the EVAP system develops a vacuum of 2 kPa (0.29 psi), the evaporative emission purge solenoid is closed and the fuel system vacuum is maintained at 2 kPa (0.29 psi).
• The PCM determines whether there is a leak in the EVAP system by monitoring the vacuum inside the fuel tank.
• The test is stopped when fuel vapor pressure exceeds predetermined limits.
DESCRIPTIONS OF MONITOR METHODS
Measure reverting pressure after depressurizing by intake manifold negative pressure and detect malfunction if reverting pressure rises largely.
MONITOR EXECUTION
Once per driving cycle.
MONITOR EXECUTION CONDITIONS (Other Monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
Evaporative emission purge solenoid monitor
Evaporative emission purge system monitor
Fuel tank differential pressure sensor monitor
Evaporative emission ventilation solenoid monitor
Fuel level sensor monitor
Fuel temperature sensor monitor

Sensor (The sensors below are determined to be normal)
Volume airflow sensor
Barometric pressure sensor
Intake air temperature sensor
Engine coolant temperature sensor
LOGIC FLOW CHARTS (Monitor Sequence)
DTC SET CONDITIONS
Remaining fuel amount is 15 - 40 percent of capacity. (fuel level sensor output voltage is 1.4 - 2.4 volts).

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.
Fuel temperature is less than 36 °C (97 °F), and with in 800 seconds have elapsed since the engine was started.
Engine coolant temperature is greater than 58 °C (136 °F).
Intake air temperature is greater than -10 °C (14 °F).
Barometric pressure is greater than 76 kPa (11 psi).
Power steering pressure switch: "OFF".
Fuel tank differential pressure sensor output voltage is 1 - 4 volts.
Pressure fluctuation is less than 647 Pa (0.094 psi).
When evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure rises in the fuel tank is less than 451 Pa (0.065 psi).
Vehicle speed is greater than or equal to 20 km/h (12.4 mph).
10 seconds have elapsed from the start of the previous monitoring.
Monitoring time: 75 - 125 seconds.

Judgment Criteria:
• Internal pressure of the fuel tank has changed greater than 785 Pa (0.144 psi) in 20 seconds after the tank and vapor line were closed.
DTC SET CONDITIONS
Remaining fuel amount is 40 - 85 percent of capacity. (fuel level sensor output voltage is 2.4 - 3.7 volts).

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 20 °C (68 °F).
Intake air temperature is greater than -10 °C (14 °F).
Fuel temperature is less than 36 °C (97 °F).
Barometric pressure is greater than 76 kPa (11 psi).
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 rises in the fuel tank is less than 324 Pa (0.047 psi).
10 seconds have elapsed from the start of the previous monitoring
Monitoring time: 10 - 14 minutes.

Judgment Criteria:
• Internal pressure of the fuel tank has changed greater than 1.96 kPa (0.285 psi) in 128 seconds after the tank and vapor line were closed.
OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-ll Drive Cycle - Procedure 1 - Evaporative Emission System Leak Monitor .
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:
• Loose fuel cap.
• Fuel cap relief pressure is incorrect.
• Evaporative emission canister seal is leaking.
• Fuel tank, purge line or vapor line seal is leaking.
• Evaporative emission ventilation solenoid dose not seal.