摘要:
A fuel tank is divided into a fuel chamber and an air chamber by a bladder diaphragm. Under a condition that both the amount of intake air Ga and the engine revolution speed NE of an internal combustion engine are kept at constant values, a vapor concentration correction factor FGPG during a fuel injection duration TAU is calculated based on a change in the air-fuel ratio detected when gas is purged from the air chamber toward an intake passage of the engine. Based on the vapor concentration correction factor FGPG, it is determined whether there is fuel leakage from the fuel chamber to the air chamber. With this determination technique, a fluctuation in the air-fuel ratio is not caused by a situation where the engine is in a transitional state, during fuel leakage detection, so that the vapor concentration correction factor FGPG assumes a proper value corresponding to the vapor concentration in the air chamber. Therefore, a false determination regarding the presence/absence of fuel leakage from the fuel chamber to the air chamber is prevented.
摘要:
A fuel vapor purge system has a canister for adsorbing fuel vapor from a fuel tank, a bypass passage bypassing the canister, and a bypass valve for controlling the state of connection of the bypass passage to a purge passage. The bypass passage is provided with a venturi so that the flow passage resistance of the bypass passage is normally greater than the flow passage resistance of the canister. The amount of flow of gas from an air chamber to an intake passage changes in accordance with the flow passage resistance of the passage. In this case, the tank internal pressure in the air chamber converges to a value corresponding to the flow passage resistance of the passage between the air chamber and the intake passage. Therefore, based on the tank internal pressure occurring before and after the supply of a drive signal to the bypass valve, it is determined whether the bypass passage has a clogged abnormality and whether the bypass valve has a fixation abnormality.
摘要:
The present invention provides an evaporated fuel system diagnostic apparatus. The evaporated fuel system diagnostic apparatus includes a malfunction determination unit which determines whether a malfunction occurs in an evaporated fuel system, by introducing a negative pressure of an intake passage into a fuel tank. An operating condition setting unit sets, when the malfunction determination unit has started the introduction of the negative pressure of the intake passage into the fuel tank, an operating condition of an internal combustion engine in a predetermined condition that causes the negative pressure of the intake passage to be within a predetermined pressure range. Further, the present invention provides a vehicle control apparatus for an automotive vehicle equipped with the evaporated fuel system diagnostic apparatus.
摘要:
The present invention provides an evaporated fuel system diagnostic apparatus. The evaporated fuel system diagnostic apparatus includes a malfunction determination unit which determines whether a malfunction occurs in an evaporated fuel system, by introducing a negative pressure of an intake passage into a fuel tank. An operating condition setting unit sets, when the malfunction determination unit has started the introduction of the negative pressure of the intake passage into the fuel tank, an operating condition of an internal combustion engine in a predetermined condition that causes the negative pressure of the intake passage to be within a predetermined pressure range. Further, the present invention provides a vehicle control apparatus for an automotive vehicle equipped with the evaporated fuel system diagnostic apparatus.
摘要:
A diagnostic apparatus for a fuel vapor purge system is provided which includes a pressure sensor that measures a pressure in a fuel tank, and which conducts leak diagnosis of a purge path based on a change in the pressure in the fuel tank and an amount of fuel vapor generated in the fuel tank. The change in the pressure is measured after sealing the purge path while providing a difference between inside pressure and outside pressure of the purge path, and the amount of fuel vapor is measured after applying an atmospheric pressure to the purge path and sealing the purge path. The diagnostic apparatus further detects a predetermined state after starting application of the atmospheric pressure to the purge path, and determines that the purge path has reached an atmospheric pressure state upon. detection of the predetermined state. The amount of fuel vapor generated in the fuel tank is measured when it is determined that the purge path has reached the atmospheric pressure state.
摘要:
The present invention provides an evaporated fuel system diagnostic apparatus. The evaporated fuel system diagnostic apparatus includes a malfunction determination unit which determines whether a malfunction occurs in an evaporated fuel system, by introducing a negative pressure of an intake passage into a fuel tank. An operating condition setting unit sets, when the malfunction determination unit has started the introduction of the negative pressure of the intake passage into the fuel tank, an operating condition of an internal combustion engine in a predetermined condition that causes the negative pressure of the intake passage to be within a predetermined pressure range. Further, the present invention provides a vehicle control apparatus for an automotive vehicle equipped with the evaporated fuel system diagnostic apparatus.
摘要:
Electricity is suppressed from flowing to a case (2) of an electric heating type catalyst (1). The electric heating type catalyst (1) is provided with a heat generation element (4) to be electrically energized to generate heat, the case (2) in which the heat generation element (4) is received, and a mat (3) inserted between the heat generation element (4) and the case (2) for insulating electricity, wherein the case (2) is formed into double pipes (24) at an upstream side and downstream side of the heat generation element (4), respectively, and an inner pipe (28) of each of the double pipes (24) is formed such that it is in contact at an upstream side or downstream side one end (25) thereof with an outer pipe (27) of each double pipe (24), with a gap being formed between the inner pipe (28) and the outer pipe (27) of each double pipe (24) at an upstream side or downstream side other end (26) of the inner pipe (28), and an insulating layer (6) for insulating electricity is provided on a surface of the case (2) from the mat (3) to the other end (26) including a range surrounded by the outer pipe (27) and the inner pipe (28) of each double pipe (24).
摘要:
The exhaust gas purifying device of an internal combustion engine includes: an electrically heated catalyst which is provided on an exhaust passage of the internal combustion engine, which purifies the exhaust gas drawn to the exhaust passage, and is warmed by electrification; and an electrification characteristic setting unit which set an electrification characteristic indicating a characteristic of an electrification resistance value in the electrically heated catalyst, in accordance with an electrification condition at a time of starting the electrification of the electrically heated catalyst. Thus, various determinations and controls relating to the electrically heated catalyst and using the electrification characteristic can be accurately performed.
摘要:
A vehicle control device applied to a vehicle including an internal combustion engine and an electrically heated catalyst which is warmed by applying a current, and includes a catalyst carrier supporting a catalyst and a carrier retention unit that retains the catalyst carrier and has an electrical insulation property. The control unit performs a control of suppressing a supply of an unburned gas from the internal combustion engine to the electrically heated catalyst so that the carrier retention unit is maintained at a lower temperature than the catalyst, when a condition for performing a fuel cut of the internal combustion engine during a deceleration is satisfied. Therefore, it is possible to suppress a rapid cooling of the catalyst, and it becomes possible to maintain a temperature of the carrier retention unit at a lower temperature than a temperature of the catalyst.
摘要:
An object of the invention is to control the penetration of condensed water into an insulation member or a heater element in an electric heating catalyst (EHC). The EHC according to the invention includes a heater element that generates heat by supply of electric current to heat a catalyst, a casing that houses the heater element, an insulation member provided between the heater element and the casing to provide electric insulation, and an electrode connected to the heater element through an electrode chamber, which is a space located between the inner wall surface of the casing and the outer circumferential surface of the heater element. The EHC is further provided with a bypass passage, one end of which is connected to a bottom part of the casing at a position upstream of the upstream end face of the insulation member. The bypass passage bypasses the insulation member.