2020 Subaru Forester P code Page 138

- evptezini less than or equal to 1.4 kPa (10.7 mmHg, 0.4 inHg)

- evptez - evptezha greater than 0.9 kPa (6.5 mmHg, 0.3 inHg)

- No fuel sloshing of over 2 l (0.53 US gal, 0.44 Imp gal) lasts for more than 40000 ms.

Judge as abnormal when all are established.

Leak Diagnosis

DTC

P0442 Evaporative Emission Control System Leak Detected (Small Leak)

P0457 Evaporative Emission Control System Leak Detected (Fuel Cap Loose/Off)

- The diagnostic consists of creating a sealed vacuum in the fuel tank and then determining the presence of leakage from the speed at which

the tank internal pressure returns to barometric pressure.

- The diagnosis is divided into the following five phases.

Mode A: (Estimated evaporation gas amount)

Calculate the tank pressure change amount (P1. when using mode A. After calculating P1, switch to mode B.

Mode B: (Negative pressure sealed)

Introduce negative pressure in the intake manifold to the tank.

Approx. 0 -> -1.4 kPa (0 -> -10.5 mmHg, 0 -> -0.4 inHg)

When the pressure above (desired negative pressure) is reached, enters Mode C. In this case, if the tank pressure does not reach the target

negative pressure, judge that there is a large leakage in the system and terminate the evaporative emission control system diagnosis.

Abnormality Judgment

Judge as NG (large leakage) when the following conditions are established.