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Home >> Subaru >> 2023 >> Ascent Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics) (2 Of 4) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P04F0: EVAP System High Pressure Purge Line (CPC2) Performance >> General Description >> Execution Condition
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Execution Condition

SECONDARY PARAMETER AND EXECUTION CONDITION - P04F0

Secondary parameters Execution condition
<high pressure side pressure system>
Battery voltage
10.9 V or more
Barometric pressure 75.06 kPa (563.1 mmHg, 22.2 inHg) or more
Intake manifold absolute pressure - Barometric pressure 30.05 kPa (225.4 mmHg, 8.9 inHg) or more
Ambient air temperature More than 4.4°C (39.9°F)
Purge control duty ratio 40% or more
Elapsed time after the switching valve in the leak check valve assembly opened 2500 ms or more
SECONDARY PARAMETER AND EXECUTION CONDITION - P04F1

Secondary parameters Execution condition
<Low pressure side pressure system>
Battery voltage
10.9 V or more
Barometric pressure 75.06 kPa (563.1 mmHg, 22.2 inHg) or more
Barometric pressure - Intake manifold absolute pressure 25.05 kPa (187.9 mmHg, 7.4 inHg) or more
Estimated ejector generation negative pressure 1.5 kPa (11.3 mmHg, 0.4 inHg) or less
Ambient air temperature More than 4.4°C (39.9°F)
Purge control duty ratio 40% or more
Elapsed time after the switching valve in the leak check valve assembly opened 2500 ms or more

GENERAL DRIVING CYCLE 

Perform the diagnosis only once after starting the engine.

DIAGNOSTIC METHOD 

When the purge control solenoid valve is duty controlled in the boost region where negative pressure is generated in the intake manifold, negative pressure reaches the CPC pressure sensor as pulsation. ECM integrates the amount of change of the pulsation, judges as OK when it is equal to or more than the predetermined value, and judges as NG when it is less than the predetermined value.

Judge as NG when the following conditions are established.

JUDGMENT VALUE SPECIFICATION

Malfunction Criteria Threshold Value DTC
<high pressure side pressure system>
Pressure pulsation valve
Less than value of Map1 P04F0
<Low pressure side pressure system>
Pressure pulsation valve
Less than value of Map2 P04F1
ATMOSPHERIC PRESSURE SPECIFICATION - MAP 1

Atmospheric pressure (kPa (mmHg, inHg)) 70 (525.1, 20.7) 80 (600.2, 23.6) 90 (675.2, 26.6) 100 (750.2, 29.5) 110 (825.2, 32.5)
Purge pulsation pressure (kPa (mmHg, inHg)) 5.31 (39.8, 1.6) 6.38 (47.9, 1.9) 7.44 (55.8, 2.2) 8.5 (63.8, 2.5) 8.5 (63.8, 2.5)
ATMOSPHERIC PRESSURE SPECIFICATION - MAP 2

Atmospheric pressure (kPa (mmHg, inHg)) 70 (525.1, 20.7) 80 (600.2, 23.6) 90 (675.2, 26.6) 100 (750.2, 29.5) 110 (825.2, 32.5)
Purge pulsation pressure (kPa (mmHg, inHg)) 25.05 (187.9, 7.4) 26.7 (200.3, 7.9) 28.35 (212.7, 8.4) 30 (225.1, 8.9) 30 (225.1, 8.9)

Time needed for diagnosis:  1620 ms

Malfunction indicator light illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.