Method of leak detection during low engine vacuum for an evaporative emission control system
US5715799A · kind A · utility
26Cited by
3References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1996 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Mar 5, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M25/0818
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A method of leak detection for an evaporative emission control system during periods of low engine vacuum includes the steps of pulsing a leak detection pump at a predetermined rate and determining whether engine vacuum level is low. The method also includes the steps of maintaining pressurization of the evaporative emission control system if the engine vacuum level is low, maintaining pressurization behind a vapor canister vent valve if the engine vacuum level is low, and detecting for leaks in the evaporative emission control system after a normal engine vacuum level is attained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.