DTC Advanced Diagnostics: P04DF: General Description

Courtesy of HONDA, U.S.A., INC.

Courtesy of HONDA, U.S.A., INC.

The fuel vapor in the fuel tank is temporarily stored in the evaporative emission (EVAP) canister and drawn into the engine through the EVAP canister purge valve. The powertrain control module (PCM) controls the amount of vapor introduced into the engine by varying the duty cycle of the EVAP canister purge valve according to the condition of the engine. If tank pressure shows large negative pressure in spite of closed EVAP canister purge valve, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type