System and method for monitoring catalyst efficiency and post-catalyst oxygen sensor performance
US8516796B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 2009 |
| Grant date | Aug 27, 2013 |
| Priority date | — |
| Expiry date | Aug 2, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A diagnostic system for an exhaust system of an engine includes a fuel control module and a diagnostic module. The fuel control module, in response to a request for a fuel inhibiting event, operates the engine in a first rich condition for a first period until a catalytic converter of the exhaust system is in a predetermined first rich state and subsequently operates the engine in a lean condition for a second period contiguous with the first period. The diagnostic module determines a catalyst efficiency of the catalytic converter based on an output of an oxygen sensor located downstream of said catalytic converter during the second period, and selectively adjusts a diagnostic status of the catalytic converter based on a comparison of the catalyst efficiency and a predetermined catalyst efficiency. The fuel inhibiting event may be a deceleration fuel-cutoff event. A related diagnostic method is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.