Patent ID: 7370642
Filing Date: 2008-05-13
Classification: F02D

Abstract:
1. A fuel vapor treatment apparatus comprising: a canister adsorbing fuel vapor evaporated in a fuel tank, the fuel vapor being to be purged into an intake passage of an internal combustion engine; a purge valve provided in a purge passage through which the fuel vapor is introduced into the intake passage from the canister, the purge valve controlling an amount of the fuel vapor which is purged into the intake passage; a measuring means for measuring a condition of the fuel vapor which is purged into the intake passage; a memory storing a fluid characteristic of the purge valve; an air-fuel ratio controlling means for controlling an opening degree of the purge valve and/or a fuel injection amount based on the fluid characteristic and a measure-result measured by the measuring means so that an air fuel ratio of the internal combustion engine becomes close to a target air-fuel ratio; and a correction means for correcting the fluid characteristic stored in the memory means in a case that a difference between an actual air-fuel ratio and the target air-fuel ratio exceeds a predetermined value.