Patent ID: 7032580

Claim:
An internal combustion engine system, the engine system comprising: an internal combustion engine, which has a combustion chamber and an intake passage connected to the combustion chamber; a fuel tank for storing fuel; a canister for storing fuel vapor generated in the fuel tank, when the engine is running, fuel vapor is permitted to flow to the intake passage from the canister, and when fuel vapor flows to the intake passage, the amount of fuel injected to the engine is corrected to suppress fluctuation of the air-fuel ratio in the engine due to the fuel vapor; an EGR mechanism for introducing part of exhaust gas exhausted from the engine to the intake passage, the EGR mechanism variably sets the EGR rate, which is the ratio of exhaust gas contained in gas introduced to the combustion chamber; a tank sealing system for sealing the fuel tank, when the pressure in the fuel tank is greater than or equal to a predetermined value, the sealing system releases gas containing fuel vapor from the fuel tank to the canister on condition that fuel vapor is flowing to the intake passage from the canister; and a controller for controlling the EGR mechanism to reduce the EGR rate when gas is released from the fuel tank to the canister.