Outline Of Diagnosis: Notes

Perform the diagnosis of leakage of fuels system and valve functions.

Fig 1: DTC P0442 Evaporative Emission Control System Leak Detected - Outline Diagram (Small Leak)

Courtesy of SUBARU OF AMERICA, INC.

In this system diagnosis, checking for leakage and valve operation is conducted by changing the fuel tank pressure, and monitoring the pressure change using the fuel tank pressure sensor. 0.04-inch diagnosis is performed in the order of mode Z, mode A, mode B, mode C and mode D, and 0.02-inch diagnosis is performed in the order of mode A, mode B, mode C, mode D and mode E.