A method of adjusting operation of an internal combustion engine includes injecting fuel into cylinders of the internal combustion engine (first fuel operation); obtaining a first fuel exhaust temperature profile during the first fuel operation; injecting two fuels into the cylinders in a duel fuel operation; obtaining a duel fuel exhaust temperature profile; and adjusting the injection quantity and/or an injection timing of one fuel in a cylinder(s), based on a difference between the first fuel exhaust temperature profile and the duel fuel exhaust temperature profile. Other methods of operating with single fuel and using sensors other than exhaust temperature sensors are disclosed.

In order to provide a highly precise and highly responsive humidity detection means with which diagnosis is easy, this control device for an internal combustion engine is characterized in that two or more sensors for detecting the humidity of the atmosphere or a gas mixed with the atmosphere are provided in the middle of the flow in an intake air passage of the internal combustion engine, at least one of these sensors being a relative humidity sensor for detecting the relative humidity, at least one other of the sensors being an absolute humidity sensor for detecting the absolute humidity, and the relative humidity sensor being arranged upstream from the absolute humidity sensor.

A method for controlling an internal combustion engine including at least one exhaust-gas aftertreatment component having an electric heating element, the electric heating element heating the exhaust-gas aftertreatment component and the exhaust gas flowing through the exhaust-gas aftertreatment component, the electric heating element briefly or permanently being acted upon by a heating current, a gas, in particular fresh air and/or exhaust gas, flowing downstream through the exhaust-gas path. In the method, a first temperature upstream from the at least one exhaust-gas aftertreatment component is ascertained, a second temperature downstream from the exhaust-gas aftertreatment component is ascertained, and the exhaust-gas mass flow of the internal combustion engine is ascertained as a function of a first temperature difference between the first and the second temperature and a heating power of the electric heating element, and the internal combustion engine is controlled as a function of the exhaust-gas mass flow.

Systems and methods for diagnosing an exhaust aftertreatment system are provided. A method includes: receiving, by a controller and for each sensor of a plurality of sensors, one or more respective degradation level indicators indicative of one or more failure levels of the sensor, each of the one or more degradation level indicators determined using a corresponding performance parameter; receiving, by the controller and for each sensor of the plurality of sensors, one or more diagnosis threshold values; determining, by the controller, a multipoint diagnosis threshold value using the one or more diagnosis threshold values associated with the plurality of sensors; detecting, by the controller, an operational state of the aftertreatment system by comparing a performance value of the aftertreatment system to the multipoint diagnosis threshold value; and causing, by the controller, an indication of the operational state of the aftertreatment system to be displayed on a display device.

An engine control system according to the present disclosure includes an oil temperature sensor and a waste gate valve control unit. The oil temperature sensor detects a temperature of an engine oil. The waste gate valve control unit controls opening and closing of a waste gate valve based on the temperature of the engine oil detected by the oil temperature sensor. More specifically, when the temperature of the engine oil detected by the oil temperature sensor is equal to or less than a predetermined threshold, the waste gate valve control unit controls the waste gate valve so that it opens.

A fuel supply system with a fuel pressure sensor includes a failure detection part which sets a first threshold value and a second threshold value which are deviated by first (smaller) and second (larger) predetermined values with respect to a target fuel pressure respectively; immediately detects a possibility of failure in the case where an absolute value of a difference between an output value of the fuel pressure sensor and the target fuel pressure exceeds an absolute value of a difference between the second threshold value and the target fuel pressure; and determines a failure of the fuel pressure sensor in the case where the absolute value of the difference between the output value of the fuel pressure sensor and the target fuel pressure has been exceeding an absolute value of a difference between the first threshold value and the target fuel pressure for a specified time or longer.

A lean operation fault detection and isolation (FDI) technique involves receiving, from a manifold absolute pressure (MAP) sensor, a measured MAP, detecting a lean operation fault where an engine is operating with a lean air/fuel ratio, estimating, using an observer, (i) an air/fuel ratio of an exhaust gas produced by the engine and (ii) the MAP, monitoring first and second residual values indicative of differences between (i) the estimated air/fuel ratio of the exhaust gas and a measured air/fuel ratio of the exhaust gas from an exhaust O2 sensor and (ii) the estimated MAP and the measured MAP from the MAP sensor, respectively, and, based on the monitoring of the first and second residual values, determining which of (i) an air intake of the engine, (ii) the exhaust O2 sensor, and (iii) a fuel injector of the engine is malfunctioning and causing the lean operation fault.

An ignition switch is turned on, and when an abnormality is detected in any of electronic control instruments or sensors, real failure is established, and a fail-safe process is performed. After a lapse of a predetermined period from the establishment of the real failure, fault determination is established, a failure level is sent, and a hybrid fail-safe process is performed. Then, when the abnormality is eliminated, the real failure is not established, and the fail-safe process of an engine is finished. Then, when the ignition switch is turned off and then again turned on, sending of the failure level to a hybrid control unit is stopped, and the hybrid fail-safe process is finished.

An ECM determines a failure exist and a failure site in a control valve device from first and second failure diagnoses. In the first failure diagnosis, a failure is determined to have occurred if an opening amount that represents an absolute value of a difference between a detected opening amount and a target opening amount of a valve body is greater than a preset threshold when the target opening amount of the valve body is constant for a predetermined time. In the second failure diagnosis, a failure is determined to have occurred if an opening amount that represents the absolute value of the difference between the opening amount of the valve body when fully open or fully closed and the detected opening amount is greater than the preset threshold when a portion rotating integrally with the valve body has been pressed against a stopper continuously for a predetermined time.

Methods and systems are provided for waking up a powertrain control module of an engine-driven vehicle during engine soak to perform an offset test of an exhaust NOx sensor. In one example, a method includes determining a duration to delay waking up the powertrain control module based on exhaust temperature at vehicle-off, waking up the powertrain control module after the duration has expired, and then initiating heating of the NOx sensor. After the NOx sensor lights off, heating continues for an additional duration before offset testing of the NOx sensor is performed.