| 摘要 |
A valve control section of a diagnostic device for an evaporated fuel processing system closes an evaporated fuel processing system at closing timing at which a value of the internal pressure detected by an internal pressure detection section reaches a preset target pressure value after a negative pressure is introduced from an inlet system to the evaporated fuel processing system. A diagnostic section of the device compares the internal pressure value at diagnostic timing which is set so as to come after the closing timing with a preset criterion threshold value so as to execute a leak diagnosis of the evaporated fuel processing system. A calculation section of the device variably sets the diagnostic timing based on the intake negative pressure value detected by the intake pressure detection section. Thus, a time period required for an early diagnosis of the leak can be optimized.
|
