Method for cold start emissions diagnostic
AssigneeGM Global Technology Operations LLC
InventorsGregory J. York, Vijay A. Ramappan, Zhijian J. Wu
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Abstract
A method for cold start emissions diagnostic of a catalytic treatment device of an internal combustion engine includes determining a torque reserve; determining a catalyst light off (CLO) state; integrating the total torque reserve over a time period established by the CLO state; determining if a value from the integration exceeds an integration threshold; and if the value from the integration exceeds the integration threshold, indicating that the cold start emissions diagnostic is positive.
Claims18
A method for cold start emissions diagnostic of a catalytic treatment device of an internal combustion engine, the method comprising:
- determining a torque;
- guiding internal combustion engine exhaust gas to the catalytic treatment device for treatment by the catalytic treatment device;
- providing an intake air temperature from a temperature sensor and concentration of combustibles of the exhaust gas from an exhaust gas sensor to a controller;
- evaluating the intake air temperature and the concentration of combustibles with the controller, the controller:
- determining a catalyst light off (CLO) state;
- integrating the total torque over a measured time period established by the CLO state;
- determining if a value from the integration exceeds an integration threshold;
- and
- indicating that the cold start emissions diagnostic is positive when the value from the integration exceeds the integration threshold.
A method for cold start emissions diagnostic of a catalytic treatment device of an internal combustion engine, the method comprising:
- determining a torque;
- guiding internal combustion engine exhaust gas to the catalytic treatment device for treatment by the catalytic treatment device;
- providing an intake air temperature from a temperature sensor and concentration of combustibles of the exhaust gas from an exhaust gas sensor to a controller;
- evaluating the intake air temperature and the concentration of combustibles with the controller, the controller:
- determining a catalyst light off (CLO) state;
- integrating the total torque over a measured time period established by the CLO state;
- determining if a value from the integration exceeds an integration threshold;
- determining a CLO enabled time period after the start of the engine;
- and
- indicating that the cold start emissions diagnostic is positive when the CLO enable time period exceeds a minimum time threshold and when the value from the integration exceeds the integration threshold.
A method for cold start emissions diagnostic of a catalytic treatment device of an internal combustion engine, the method comprising:
- determining a torque;
- guiding internal combustion engine exhaust gas to the catalytic treatment device for treatment by the catalytic treatment device;
- providing an intake air temperature from a temperature sensor and concentration of combustibles of the exhaust gas from an exhaust gas sensor to a controller;
- evaluating the intake air temperature and the concentration of combustibles with the controller, the controller:
- determining a catalyst light off (CLO) state;
- integrating the total torque over a measured time period established by the CLO state;
- determining if a value from the integration exceeds an integration threshold;
- determining a CLO enabled time period after the start of the engine;
- and
- determining if the CLO enabled time period exceeds a minimum time threshold.
Dependencies are inferred from the claim text.