Claims
- 1. A diagnostic apparatus for an evaporated fuel system in which fuel vapor, evaporated from fuel within a fuel tank, is adsorbed, and the adsorbed fuel vapor is purged into an intake passage of an internal combustion engine via a purge passage by using a negative pressure of the intake passage, comprising:a malfunction determination unit determining whether a malfunction in the evaporated fuel system occurs, based on an internal pressure in the evaporated fuel system after the evaporated fuel system pressure reaches a reference pressure by introduction of the negative pressure of the intake passage into the fuel tank; and an upper-limit changing unit changing, when the malfunction determination unit performs the determination regarding the malfunction, an upper-limit value of an opening angle for a throttle valve to a second upper-limit value that is smaller than a first upper-limit value of the throttle valve opening angle used when the malfunction determination unit does not perform the determination.
- 2. The diagnostic apparatus according to claim 1, wherein the upper-limit changing unit modifies the second upper-limit value of the throttle valve opening angle in accordance with a detected atmospheric pressure.
- 3. A vehicle control apparatus for an automotive vehicle equipped with an internal combustion engine, a secondary power source, an evaporated fuel system and an evaporated fuel system diagnostic apparatus, wherein the evaporated fuel system diagnostic apparatus comprises:a malfunction determination unit determining whether a malfunction in the evaporated fuel system occurs, based on an internal pressure produced in the evaporated fuel system after a reference pressure is reached by the evaporated fuel system pressure by introduction of a negative pressure of an intake passage of the engine into a fuel tank; and an upper-limit changing unit changing, when the malfunction determination unit performs the determination regarding the malfunction, an upper-limit value of an opening angle for a throttle valve to a second upper-limit value that is smaller than a first upper-limit value of the throttle valve opening angle used when the malfunction determination unit does not perform the determination, the vehicle control apparatus comprising: an output force changing unit increasing, when an output force of the engine is decreased after the upper-limit changing unit changes the upper-limit value of the throttle valve opening angle to the second upper-limit value, an output force of the secondary power source by an amount corresponding to the decrease of the engine output force.
Priority Claims (2)
Number |
Date |
Country |
Kind |
11-301612 |
Oct 1999 |
JP |
|
2000-111155 |
Apr 2000 |
JP |
|
CROSS REFERENCE TO RELATED PATENT APPLICATION
This patent application is a divisional application of Ser. No. 09/693,453, filed Oct. 20, 2000 Now U.S. Pat. No. 6,575,146, all of which is incorporated herein by reference.
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