Systems and methods for determining fuel release from a fuel injector

Patent metadata

Field	Value
Publication number	US-10337443-B1
Application number	US-201815873390-A
Country	US
Kind code	B1
Filing date	Jan 17, 2018
Priority date	Jan 17, 2018
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

Methods and systems for evaluating whether or not a fuel amount that is greater than a threshold has been release to an engine via fuel injectors when the fuel injectors are commanded off are presented. In one example, an oxygen sensor is activated and engine cranking is prevented until a pumping current of the oxygen sensor is proportionate to a concentration of oxygen sensed via the oxygen sensor so that released fuel may be observed during engine starting.

First claim

The invention claimed is:

1. An engine method, comprising:
positively identifying that one or more fuel injectors of an engine have released greater than a threshold amount of fuel to the engine while the engine was stopped and while engine fuel injectors were commanded off, the positive identification determined via a controller evaluating an engine fuel-air ratio estimate produced during engine cranking and run-up, the engine fuel-air ratio produced via an oxygen sensor having a temperature greater than or equal to a temperature where a pumping current of the oxygen sensor is proportionate to a concentration of oxygen sensed via the oxygen sensor; and
adjusting an actuator via the controller in response to the positive identification.

2. The method of claim 1 , further comprising negatively identifying that the one or more fuel injectors have released greater than the threshold amount of fuel to the engine while the engine was stopped and while engine fuel injectors were commanded off, the negative identification determined via the controller evaluating the engine fuel-air ratio estimate produced during engine cranking and run-up being greater than a threshold.

3. The method of claim 1 , where the positive identification is based on the engine fuel-air ratio being greater than a threshold during the engine cranking and run-up.

4. The method of claim 1 , further comprising:
integrating the fuel-air ratio estimate produced during engine cranking and run-up.

5. The method of claim 4 , where the positive identification is based on the integrated engine fuel-air ratio being greater than a threshold.

6. The method of claim 1 , further comprising:
identifying a cylinder in which the one or more fuel injectors released greater than the threshold amount of fuel.

7. The method of claim 1 , further comprising:
not identifying that the one or more fuel injectors of the engine have released greater than the threshold amount of fuel when a temperature of the engine is less than a threshold.

8. The method of claim 1 , further comprising:
identifying a first cylinder to fire during the engine cranking and run-up and selectively deactivating engine cylinders based on the first cylinder to fire in response to an indication of more than a threshold amount of fuel being released from the one or more fuel injectors.

9. A system, comprising:
an engine including at least one fuel injector and an oxygen sensor positioned in an exhaust manifold;
a controller storing executable instructions in non-transitory memory that, when executed, cause the controller to:
adjust an engine starting procedure after identifying that the at least one fuel injector released greater than a threshold amount of fuel into the engine while the engine was stopped and while the at least one fuel injector was commanded off, the identification performed during cranking and run-up of the engine during an engine start.

10. The system of claim 9 , further comprising additional instructions to determine a maximum fuel-air ratio during the cranking and run-up.

11. The system of claim 10 , where the identification is based on the maximum fuel-air ratio exceeding a threshold.

12. The system of claim 9 , where adjusting the engine starting procedure includes deactivating an engine cylinder.

Assignees

• Ford Global Tech Llc

Inventors

• Ulrey Joseph
• Uhrich Michael
• Pursifull Ross
• Schwochert Steven

Classifications

• F02D41/221

  relating to the failure of actuators or electrically driven elements · CPC title

• F02D13/0203

  Variable control of intake and exhaust valves · CPC title

• F02D41/1454

  the characteristics being an oxygen content or concentration or the air-fuel ratio · CPC title

• F02D41/1445

  the characteristics being related to the exhaust flow · CPC title

• F02D41/0087 Primary

  Selective cylinder activation, i.e. partial cylinder operation (deceleration cut-off F02D41/123) · CPC title