Method for variable position exhaust tuning valve diagnostics

Patent metadata

Field	Value
Publication number	US-10844762-B2
Application number	US-201715792666-A
Country	US
Kind code	B2
Filing date	Oct 24, 2017
Priority date	Oct 24, 2017
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

Methods and systems are provided for adjusting and troubleshooting an adjustable exhaust valve of a variable exhaust tuning system. In one example, a method may include comparing engine startup conditions to engine conditions of a last engine off event, adjusting a position of the adjustable exhaust valve, and providing a diagnostic summary to a vehicle operator based upon the results of the comparison and adjustment.

First claim

The invention claimed is:

1. A method for an adjustable engine-exhaust valve, comprising:
via a controller including executable instructions stored in non-transitory memory,
monitoring engine off time and checking for one or more entry conditions at engine startup,
operating with the adjustable engine-exhaust valve being stuck, and responsive to the adjustable engine-exhaust valve being stuck:
during selected engine start-up conditions and after sufficient engine-off time, setting an error code associated with the one or more entry conditions upon an exhaust temperature sensed via a temperature sensor reaching an exhaust temperature threshold,
commanding the adjustable engine-exhaust valve to a first commanded valve position, and
based upon a current valve position of the adjustable engine-exhaust valve being within a tolerance band of a first commanded valve position, clearing the error code.

2. The method of claim 1 , wherein the one or more entry conditions comprises any of
an actuator of the adjustable exhaust valve reporting a stuck status;
a humidity sensor reading a water concentration higher than a threshold water concentration at the most recent engine-off time;
a vehicle soak time being greater than a calculated amount of time for ice formation while engine is off;
a current ambient temperature being either greater than or less than a threshold temperature;
and an exhaust volume level failing to fall between a first volume threshold and a second volume threshold.

3. The method of claim 2 , further comprising calculating the calculated amount of time for ice formation based upon a difference in temperature of exhaust at an engine-off event and at the next engine-on event.

4. The method of claim 2 , further comprising measuring the exhaust volume level via a microphone attached to a bottom surface of the vehicle.

5. The method of claim 1 , wherein the exhaust temperature is measured by temperature sensors within the walls of the adjustable exhaust valve.

6. The method of claim 1 , wherein the current valve position of the adjustable exhaust valve is not within the tolerance band of the first commanded valve position then adding a valve command counter.

7. The method of claim 6 , further comprising after adding the valve command counter then again commanding the adjustable exhaust valve to the first commanded valve position.

8. The method of claim 6 , further comprising upon reaching a command counter threshold latching a valve error code.

9. The method of claim 6 , further comprising alerting a vehicle operator within the cabin of the vehicle to the valve error code via a volume and/or visual alert.

10. A method for troubleshooting an adjustable exhaust valve of an engine, comprising:
via a controller including executable instructions stored in non-transitory memory,
monitoring engine off time and checking for one or more entry conditions at engine startup,
executing a stuck valve check,
operating with exhaust temperature rising up to and above an exhaust temperature threshold;
setting a stuck valve error code associated with the one or more entry conditions upon the exhaust temperature sensed via a temperature sensor reaching the exhaust temperature threshold,
running a valve self-healing routine,
checking a first time for a stuck valve code of the adjustable exhaust valve, and
based upon failing to receive the stuck valve code, clearing the error code.

11. The method of claim 10 , wherein the valve self-healing routine comprises toggling the adjustable exhaust valve between open and closed states a programmable number of times.

12. The method of claim 10 , further comprising issuing the stuck valve code at an actuator of the adjustable exhaust valve when the actuator cannot move.

13. The method of claim 10 , further comprising based upon receiving the stuck valve code, counting a first self-healing counter.

14. The method of claim 13 , further comprising running the self-healing routine again and checking an additional time for the stuck valve code.

15. A device for adjusting and diagnosing a valve position of a post-catalyst variable exhaust tuning system to control an exhaust backpressure, comprising:
a resonator fluidically connected to a muffler having a first and a second muffler exhaust port,
an adjustable exhaust valve included within the first muffler exhaust port adjusted via a valve actuator communicatively coupled to a controller, a positioning sensor included within the adjustable exhaust valve, the controller including executable instructions stored in non-transitory memory that cause the controller to:
check for one or more entry conditions at engine startup,
operate an engine with the adjustable exhaust valve being stuck, and responsive to the adjustable exhaust valve being stuck:
during selected engine start-up conditions and after sufficient engine-off time, set an error code associated with the one or more entry conditions upon an exhaust temperature reaching an exhaust temperature threshold,
command the adjustable exhaust valve to a first commanded valve position, and
based upon a current valve position of the adjustable exhaust valve being within a tolerance band of a first commanded valve position, clear the error code.

16. The device of claim 15 , wherein the adjustable exhaust valve is a butterfly valve.

17. The device of claim 15 , further comprising a humidity sensor to estimate an engine off estimation of a mass of water remaining in the device.

18. The device of claim 15 , further comprising a rotational rod connected to both the adjustable exhaust valve and the valve actuator for rotating the adjustable exhaust valve.

19. The device of claim 15 , further comprising a microphone attached to a bottom surface of the vehicle for obtaining volume input of the variable exhaust tuning system.

20. The device of claim 15 , further comprising a pressure and temperature sensor included within the muffler for tracking both temperature and pressure of exhaust gases of the variable exhaust tuning system.

Assignees

• Ford Global Tech Llc

Inventors

• Dadam Sumanth
• Sharma Sanyam
• Jentz Robert Roy

Classifications

• F01N2550/00

  Monitoring or diagnosing the deterioration of exhaust systems · CPC title

• F01N13/04

  having two or more silencers in parallel, e.g. having interconnections for multi-cylinder engines · CPC title

• F01N1/168

  for controlling or modifying silencing characteristics only · CPC title

• F01N11/00

  Monitoring or diagnostic devices for exhaust-gas treatment apparatus · CPC title

• F01N2240/36

  an exhaust flap · CPC title