DTC P0496: Evaporative Emission (EVAP) System High Purge Flow: General Description

The engine control module (ECM) adjusts the amount of fuel vapor sent to the engine by controlling the evaporative emission (EVAP) canister purge valve. If the EVAP canister purge valve is stuck open, engine vacuum flows into the purge line before purge control starts when starting the engine. The ECM monitors the fuel tank pressure (FTP) sensor output when purge control starts. If the FTP sensor output indicates negative pressure, the ECM detects a malfunction in the EVAP canister purge valve, and a DTC is stored.

MONITOR EXECUTION, SEQUENCE, DURATION, DTC TYPE, OBD STATUS

Execution	Once per driving cycle
Sequence	None
Duration	10 seconds or more
DTC Type	Two drive cycles, MIL ON
OBD Status	N/A

ENABLE CONDITIONS CHART

Condition

Minimum

Maximum

Elapsed time before starting the engine

10 seconds

Initial condition A⁽¹⁾

18°F (10°C)

Initial condition B⁽²⁾

18°F (10°C)

Initial engine coolant temperature

40°F (5°C)

95°F (35°C)

Initial intake air temperature

40°F (5°C)

95°F (35°C)

Engine coolant temperature before EVAP purge control starts

149°F (65°C)

MAP value

81 kPa (24.0 in.Hg, 610 mmHg)

Battery voltage

10.5 V

Fuel trim

0.69

1.47

Fuel feedback

Closed loop

No active DTCs

P0107, P0108, P0111, P0112, P0113, P0116, P0117, P0118, P0125, P0443, P0451, P0452, P0453, P0498, P0499, P1109, P1116, P1128, P1129, P1454, P2227, P2228, P2229

⁽¹⁾	Initial engine coolant temperature minus initial intake air temperature

⁽²⁾	Initial intake air temperature minus current intake air temperature