Claims
- 1. A determining the amount of NOx stored in a NOx trap comprising:
determining a change in the oxygen concentration between an exhaust air/fuel ratio entering the NOx trap and exiting the NOx trap to determine the amount of NOx absorbed in the trap.
- 2. A method for determining the amount of hydrogen used in a water gas reaction in a reaction device disposed in an exhaust of an engine comprising determining a mathematical difference between an air/fuel ratio upstream of the device and an air/fuel ratio measured downstream of the device.
- 3. The method recited in claim 2 wherein the reaction device is a lean NOx trap.
- 4. The method recited in claim 2 wherein the reaction device is a catalytic converter.
- 5. A method for use in purging NOx from a NOx trap, comprising:
determining a change in the oxygen concentration between an exhaust air/fuel ratio entering the NOx trap and exiting the NOx trap, such determining providing an indication of the amount of NOx absorbed in the trap; and correcting such determined change for water gas shift reaction effects in such change in oxygen concentration determination, such effects being measured by determining the amount of hydrogen used in a water gas reaction in a NOx trap. puring such trap in accordance with the correction.
- 6. A method for use in purging a NOx trap comprising:
determining a change in the oxygen concentration between an exhaust air/fuel ratio entering the NOx trap and exiting the NOx trap to determine the amount of NOx absorbed in the trap; and correcting such determination for water gas shift reaction effects in such change in oxygen concentration determination, such effects being measured by determining a mathematical difference between an air/fuel ratio upstream of the trap and an air/fuel ratio measured downstream of the NOx trap.
RELATED APPLICATIONS
[0001] This patent application is a continuation in part of our co-pending application Ser. No. 09/783,351 filed Feb. 14, 2001, entitled “METHOD FOR CORRECTING AN EXHAUST GAS OXYGEN SENSOR”, assigned to the same assignees as the present application, the benefit of the filing date of which is claimed in this application under 35 U.S.C. 120 as to common subject matter claimed in this application.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09783351 |
Feb 2001 |
US |
Child |
10016942 |
Dec 2001 |
US |