Fault diagnosis apparatus for a fuel evaporative emission suppressing system
US5575267A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1995 |
| Grant date | Nov 19, 1996 |
| Priority date | — |
| Expiry date | Sep 29, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A fault diagnosis apparatus for detecting a fault in a fuel evaporative emission suppressing system comprises an electronic control unit. When fault diagnosis execution conditions are fulfilled, the electronic control unit stores an average of integral term values for air-fuel ratio feedback control, operating position of an idling speed control valve, and engine speed, and then actuates a purge control valve of the suppressing system so that the valve opens. In a predetermined time period after the actuation of the purge control valve, the integral term average and the like are stored again. If any changes of the integral term average and other values caused by the actuation of the purge control valve are detected, the suppressing system is concluded to be normal. If no changes are detected, on the other hand, the suppressing system is concluded to be faulty.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.