Ambient humidity detection transmission shifts

Patent metadata

Field	Value
Publication number	US-9664594-B2
Application number	US-201514626193-A
Country	US
Kind code	B2
Filing date	Feb 19, 2015
Priority date	Feb 19, 2015
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

Various method for operating an engine responsive to transmission shifts under non-fueling conditions are provided. In one example, a method of operating an internal combustion engine comprises deactivating at least one engine cylinder, performing a diagnostic while the at least one engine cylinder is deactivated and while the engine is operating under high load, predicting a transmission shift, and responsive to the predicted transmission shift, reducing engine load below the high load and terminating the diagnostic.

First claim

The invention claimed is:

1. A method of operating an internal combustion engine, comprising:
deactivating at least one engine cylinder;
performing a diagnostic while the at least one engine cylinder is deactivated and while the engine is operating under high load;
predicting a transmission shift; and
responsive to the predicted transmission shift, reducing engine load below the high load and terminating the diagnostic, wherein predicting the transmission shift includes observing vehicle acceleration, and wherein reducing the engine load below the high load includes reducing an intake throttle opening.

2. The method of claim 1 , wherein predicting the transmission shift further includes determining whether a transmission shift request flag has been set in an engine controller, the flag indicating whether the transmission shift will occur.

3. The method of claim 1 , wherein predicting the transmission shift further includes observing a position of one or both of an accelerator pedal and a brake pedal.

4. The method of claim 1 , wherein the at least one engine cylinder is deactivated responsive to deceleration fuel shut-off.

5. The method of claim 1 , further comprising responsive to reducing the engine load below the high load and terminating the diagnostic, reactivating the at least one engine cylinder.

6. The method of claim 1 , wherein the diagnostic detects ambient humidity via an oxygen sensor.

7. The method of claim 6 , wherein the oxygen sensor is an intake gas oxygen sensor.

8. The method of claim 6 , further comprising adjusting one or more engine operating parameters based on the detected ambient humidity.

9. The method of claim 1 , further comprising responsive to reducing the engine load below the high load and terminating the diagnostic, performing the predicted transmission shift.

10. An engine method, comprising:
while operating an engine with a cylinder deactivated and engine load above an upper threshold, generating a diagnostic based on operating conditions over a duration;
responsive to a predicted transmission shift occurring before a completion of the duration, terminating the diagnostic; and
indicating to an operator results of the diagnostic only when the diagnostic is completed.

11. The engine method of claim 10 , further comprising responsive to occurrence of the predicted transmission shift, while operating the engine with the cylinder deactivated and the engine load above the upper threshold, completing the diagnostic.

12. The engine method of claim 11 , wherein completing the diagnostic includes resuming the diagnostic from where the diagnostic was terminated.

13. The engine method of claim 11 , wherein completing the diagnostic includes restarting the diagnostic.

14. The engine method of claim 10 , wherein the diagnostic detects ambient humidity via an oxygen sensor.

15. An engine method, comprising:
deactivating at least one engine cylinder responsive to deceleration fuel shut-off;
opening an intake throttle of an engine;
detecting ambient humidity via an oxygen sensor with the at least one engine cylinder deactivated and the intake throttle opened; and
ceasing ambient humidity detection responsive to predicting a transmission shift with the at least one engine cylinder deactivated and the intake throttle opened.

16. The engine method of claim 15 , wherein predicting the transmission shift includes determining whether a transmission shift request flag has been set in an engine controller, the flag indicating whether the transmission shift will occur.

17. The engine method of claim 15 , further comprising:
closing the intake throttle of the engine responsive to predicting the transmission shift;
performing the transmission shift; and
completing the ambient humidity detection with the at least one engine cylinder deactivated and the intake throttle opened.

18. The engine method of claim 17 , further comprising adjusting one or more engine operating parameters based on the completed ambient humidity detection.

19. A method of operating an internal combustion engine, comprising:
deactivating at least one engine cylinder;
performing a diagnostic while the at least one engine cylinder is deactivated and while the engine is operating under high load;
predicting a transmission shift; and
responsive to the predicted transmission shift, reducing engine load below the high load and terminating the diagnostic, wherein reducing the engine load below the high load includes reducing an intake throttle opening.

20. A method of operating an internal combustion engine, comprising:
deactivating at least one engine cylinder;
performing a diagnostic while the at least one engine cylinder is deactivated and the engine operates under high load;
predicting a transmission shift;
responsive to the predicted transmission shift, reducing engine load below the high load and terminating the diagnostic; and
responsive to reducing the engine load below the high load and terminating the diagnostic, performing the predicted transmission shift.

Assignees

• Ford Global Tech Llc

Inventors

• Makled Daniel A
• Surnilla Gopichandra
• Doering Jeffrey Allen
• Shu brian
• Smith Stephen B

Classifications

• B60W10/06 Primary

  including control of combustion engines · CPC title

• B60W2540/10

  Accelerator pedal position · CPC title

• B60W2030/18081

  With torque flow from driveshaft to engine, i.e. engine being driven by vehicle · CPC title

• B60W2520/105

  Longitudinal acceleration · CPC title

• B60W40/02

  related to ambient conditions · CPC title