Failure determination system and method for internal combustion engine and engine control unit
US6763707B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 2002 |
| Grant date | Jul 20, 2004 |
| Priority date | — |
| Expiry date | Dec 26, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A failure determination system and method for an internal combustion engine and an engine control unit are provided which are capable of properly determining a failure of a variable valve mechanism for inactivating a valve system associated with at least one of cylinders during a predetermined operation of the engine, by discriminating a misfire caused by the failure of the mechanism from a normal misfire. Fuel injection valves inject fuel for each cylinder and oxygen concentration of exhaust gases is detected. A misfire condition is detected on a cylinder-by-cylinder basis. Fuel injection to a misfiring cylinder is stopped. A failure of the mechanism is determined, when a parameter based on the oxygen concentration detection indicates a richer value of an actual air-fuel ratio of the exhaust gases than a predetermined reference value does, under a condition of the fuel injection being stopped.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.