Patent application number | Description | Published |
20140202426 | METHODS AND SYSTEMS FOR HUMIDITY DETECTION VIA AN EXHAUST GAS SENSOR - Various methods and system are described for determining ambient humidity via an exhaust gas sensor disposed in an exhaust system of a variable displacement engine. A reference voltage of a sensor coupled to an inactive engine bank is modulated between a first and second voltage to estimate ambient humidity. Concurrently, a reference voltage of a sensor coupled to an active engine bank is modulated between the first and second voltage, or at the first voltage, to estimate fuel alcohol content, or exhaust air-fuel ratio, respectively. | 07-24-2014 |
20140202437 | METHODS AND SYSTEMS FOR HUMIDITY AND PCV FLOW DETECTION VIA AN EXHAUST GAS SENSOR - Methods and systems are provided for estimating a PCV flow to an engine based on the output of an exhaust gas oxygen sensor. During DFSO conditions, a reference voltage of the sensor is modulated initially with an intake throttle open and then with the intake throttle closed. PCV flow leaking past the piston valves in an aging engine, as well as an ambient humidity estimate, are inferred based on the outputs of the sensor during the modulating with the intake throttle open and closed. | 07-24-2014 |
20140311447 | HUMIDITY AND FUEL ALCOHOL CONTENT ESTIMATION - Methods and systems for an engine system including an exhaust gas sensor are disclosed. In one example, under a first engine fueling condition, an air-fuel ratio correction factor is determined based on an expected air-fuel ratio and an actual air-fuel ratio. During a second engine fueling condition and a third engine non-fueling condition, fuel alcohol content and ambient humidity, respectively, are determined based on the exhaust gas sensor and corrected based on the air-fuel ratio correction factor. | 10-23-2014 |
20150075502 | METHODS AND SYSTEMS FOR AN INTAKE OXYGEN SENSOR - Methods and systems are provided for adjusting a reference voltage for an intake manifold oxygen sensor based on ingestion of hydrocarbons from a fuel system canister and/or an engine crankcase. During conditions when purge or crankcase ventilation hydrocarbons are ingested in the intake aircharge, the intake oxygen sensor is transitioned from operating at a lower reference voltage to a higher reference voltage where the effects of the ingested hydrocarbons on the sensor output are nullified. An EGR dilution of the intake aircharge is estimated based on the output of the sensor at the higher reference voltage while an amount of hydrocarbons ingested is estimated based on a difference between sensor outputs at the higher and lower reference voltages. | 03-19-2015 |
20150075503 | METHODS AND SYSTEMS FOR AN INTAKE OXYGEN SENSOR - Methods and systems are provided for adjusting a reference voltage for an intake manifold oxygen sensor based on ingestion of hydrocarbons from a fuel system canister and/or an engine crankcase. During conditions when purge or crankcase ventilation hydrocarbons are ingested in the intake aircharge, the intake oxygen sensor is transitioned from operating at a lower reference voltage to a higher reference voltage where the effects of the ingested hydrocarbons on the sensor output are nullified. An EGR dilution of the intake aircharge is estimated based on the output of the sensor at the higher reference voltage while an amount of hydrocarbons ingested is estimated based on a difference between sensor outputs at the higher and lower reference voltages. | 03-19-2015 |
20150076134 | METHODS AND SYSTEMS FOR ADJUSTING HEATER POWER OF AN OXYGEN SENSOR TO REDUCE DEGRADATION FROM WATER - Methods and systems are provided for adjusting heater power of an oxygen sensor. In one example, a method for an engine includes adjusting heater power of a heating element of the oxygen sensor when the heater power increases by a threshold amount. The method includes subsequently increasing heater power back to a baseline power level responsive to a temperature of the heating element. | 03-19-2015 |
20150192084 | METHODS AND SYSTEMS FOR FUEL ETHANOL CONTENT DETERMINATION VIA AN OXYGEN SENSOR - Methods are provided for accurately learning part-to-part variability of an intake or exhaust oxygen sensor. A correction factor is learned based on a sensor reading in dry air conditions, the dry air reading learned by applying a higher reference voltage to the sensor. An ethanol transfer function is then adjusted based on the learned correction factor so as to improve the accuracy of combusted fuel ethanol content estimation. | 07-09-2015 |
20150192085 | METHODS AND SYSTEMS FOR FUEL ETHANOL CONTENT DETERMINATION VIA AN OXYGEN SENSOR - Methods are provided for accurately learning part-to-part variability of an intake or exhaust oxygen sensor. A correction factor is learned based on sensor readings at voltages above and below a voltage corresponding to dry air conditions. An ethanol transfer function is then adjusted based on the learned correction factor so as to improve the accuracy of combusted fuel ethanol content estimation. | 07-09-2015 |