Abstract: An ECU executes (300) a program including a step (S202) of opening an electromagnetic ASV (232) while a vacuum pressure ASV (1) and a vacuum pressure ASV (2) are controlled so as to be closed, and an air pump (200) is controlled so as to be stopped in a case where an air amount GA that is an amount of air introduced into an engine (100) is equal to or larger than a predetermined air amount GA (0), and a coolant temperature TW at the starting time of the engine is equal to or higher than a predetermined coolant temperature TW (0) (“YES” in step S200); a step (S204) of detecting a pressure; a step (S206) of closing the electromagnetic ASV; and a step (S402) of determining that failure has occurred in at least one of the vacuum pressure ASV (1) and the vacuum pressure ASV (2), that is, one of the vacuum pressure ASV (1) and the vacuum pressure ASV (2) remains in an opened state and cannot be closed when there is a pulsation of the pressure that is detected while the electromagnetic ASV is opened (“YES” in step S

Abstract: An exhaust purification catalyst warm-up system has an air pump that supplies air upstream from an exhaust purifying catalyst, disposed in an exhaust pipe of an internal combustion engine, the pump supplying air when the exhaust purifying catalyst is being warmed up. The exhaust purification catalyst warm-up system also has an atmospheric pressure sensor that detects the atmospheric pressure, wherein correction is performed so that the degree of fuel increase is smaller, the higher is the atmospheric pressure detected by the atmospheric pressure sensor.

Abstract: An ECU executes a program including a step (S102) of limiting the maximum opening amount of a throttle valve to TH (1) when failure has occurred in a pressure sensor (“YES” in step S100); a step (S202) of limiting the maximum opening amount to TH (2) when open failure has occurred in at least one of two vacuum pressure ASVs provided for banks of a V-type engine, and an electromagnetic ASV (“YES” in step S200); a step (S302) of limiting the maximum opening amount to TH (3) when open failure has occurred in both of the vacuum pressure ASVs (“YES” in step S300); a step (S402) of limiting the maximum opening amount to TH (4) when open failure has occurred in one of the vacuum pressure ASVs (“YES” in step S400); and a step (S502) of reducing the throttle valve opening amount TH to the limited maximum opening amount.

Abstract: An exhaust purification catalyst warm-up system has an air pump that supplies air upstream from an exhaust purifying catalyst, disposed in an exhaust pipe of an internal combustion engine, the pump supplying air when the exhaust purifying catalyst is being warmed up. The exhaust purification catalyst warm-up system also has an atmospheric pressure sensor that detects the atmospheric pressure, wherein correction is performed so that the degree of fuel increase is smaller, the higher is the atmospheric pressure detected by the atmospheric pressure sensor.

Abstract: An ECU executes (300) a program including a step (S202) of opening an electromagnetic ASV (232) while a vacuum pressure ASV (1) and a vacuum pressure ASV (2) are controlled so as to be closed, and an air pump (200) is controlled so as to be stopped in a case where an air amount GA that is an amount of air introduced into an engine (100) is equal to or larger than a predetermined air amount GA (0), and a coolant temperature TW at the starting time of the engine is equal to or higher than a predetermined coolant temperature TW (0) (“YES” in step S200); a step (S204) of detecting a pressure; a step (S206) of closing the electromagnetic ASV; and a step (S402) of determining that failure has occurred in at least one of the vacuum pressure ASV (1) and the vacuum pressure ASV (2), that is, one of the vacuum pressure ASV (1) and the vacuum pressure ASV (2) remains in an opened state and cannot be closed when there is a pulsation of the pressure that is detected while the electromagnetic ASV is opened (“YES” in step S

Abstract: An ECU executes a program including a step (S102) of limiting the maximum opening amount of a throttle valve to TH (1) when failure has occurred in a pressure sensor (“YES” in step S100); a step (S202) of limiting the maximum opening amount to TH (2) when open failure has occurred in at least one of two vacuum pressure ASVs provided for banks of a V-type engine, and an electromagnetic ASV (“YES” in step S200); a step (S302) of limiting the maximum opening amount to TH (3) when open failure has occurred in both of the vacuum pressure ASVs (“YES” in step S300); a step (S402) of limiting the maximum opening amount to TH (4) when open failure has occurred in one of the vacuum pressure ASVs (“YES” in step S400); and a step (S502) of reducing the throttle valve opening amount TH to the limited maximum opening amount.

Abstract: A fuel evaporative emission treatment system includes a canister which has an evaporative fuel introduction part arranged for communication with a fuel tank, an evaporative fuel emission part arranged for communication with an intake system of an engine, and a vent part arranged for communication with the atmosphere, and which absorbs the evaporative fuel. The fuel evaporative emission treatment system includes a vent pipe having a first passage communicating to the vent part of the canister and to the atmosphere, a first solenoid valve for opening and closing the first passage, an air filter for cleaning atmospheric air flowing thereinto, the filter being provided on the first passage on the side remote from the canister with respect to the first solenoid valve, and a one-way valve or lead valve which defines a second passage communicating to the vent part of the canister. The valve is opened at fueling.

Abstract: The fuel storage system includes a control valve having a valve body which is movable along the inner circumferential wall surface of a filler pipe and which defines a passage isolated from the inner space of the filler pipe. A fuel tank and a canister communicate with each other via a main vapor line. When a fuel cap is attached to the filler port of the filler pipe, the valve body of the control valve is pushed by the fuel cap to be shifted away from the filler port, whereby a first sub-vapor line extending between the fuel tank and the control valve via the passage defined by the valve body is communicated to a second sub-vapor line extending between the control valve and the middle part of the main vapor line, permitting evaporative fuel gas to be introduced from the fuel tank into the canister.

Abstract: A fuel evaporative emission suppressing apparatus includes an electronic control unit (50) for executing a purge control subroutine wherein the driving duty factor of a purge control valve (46) for controlling the purge air flow rate is subjected to variable control. In the purge control subroutine, the electronic control unit compares the air-fuel ratio correction coefficient (K.sub.IFB) calculated in an air-fuel ratio feedback control subroutine with a target air-fuel ratio correction coefficient (K.sub.IOBJ) for purge air introduction period, increases or decreases a purge correction coefficient (K.sub.PFB) in accordance with the comparison result, and actuates the purge control valve with a duty factor (D.sub.PRG) obtained by multiplying a basic duty factor (D.sub.T), retrieved from an engine rotational speed-volumetric efficiency map, by the purge correction coefficient.

Abstract: A fuel evaporative emission treatment system installed in an engine fuel system has a canister for adsorbing evaporative fuel, a vent hose connecting a fuel tank and the canister, and a vent circulation hose connecting the vent hose and a filler neck of the fuel tank, and the sectional areas of the vent hose and vent circulation hose are set so that the ratio thereof may be a proper value. The negative pressure produced in the filler neck due to aspiration induced by refueling is canceled out by the pressure of fuel gas circulated to the filler neck through the vent circulation hose, whereby the internal pressure of the filler neck is controlled to a value appropriately smaller than the atmospheric pressure. Thus, inflow of the outside air into the filler neck, and thus generation of evaporative fuel gas, can be suppressed, and also the outflow of evaporative fuel gas from the filler neck is suppressed.