D EVAP Leak Check

1) While actuating the leak detection pump, the ECM turns ON the vent valve in order to introduce a vacuum into the canister.

2) When the pressure in the system stabilizes, the ECM compares this pressure and the 0.02 in. pressure in order to check for a leakage.

3) If the detection value is below the 0.02 in. pressure, the ECM determines that there is no leakage.

4) If the detection value is above the 0.02 in. pressure and near atmospheric pressure, the ECM determines that there is a gross leakage (large hole) and stores DTC P0455 in its memory.

5) If the detection value is above the 0.02 in. pressure, the ECM determines that there is a small leakage and stores DTC P0456 in its memory.

Purge VSV (OFF)

Purge VSV (OFF)

U6UXAZ3C

Purge VSV

Vent Valve

Pump Motor

OFF (Vent)

ON OFF

Atmospheric Pressure

System Pressure

0.02 in. Pressure

OFF (Vent)

ON OFF

Atmospheric Pressure

0.02 in. Pressure

EVAP Leak Check

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