A gas detection device includes: an element portion; a voltage applying unit configured to apply a voltage across a first electrode and a second electrode on surfaces of a solid electrolyte; a current detecting unit configured to detect an output current flowing between the first electrode and the second electrode; and a measurement control unit. The measurement control unit acquires a parameter which has a correlation with a degree of change of the output current increasing as a concentration of sulfur oxides in an exhaust gas increases based on the output current, and performs determination of whether the concentration of sulfur oxides in the exhaust gas is equal to or higher than a predetermined value or detection of the concentration of sulfur oxides in the exhaust gas based on the acquired parameter.

A gas detection device includes a temperature control part configured to control an amount of energization to a heater so that an impedance of an element part matches a target impedance, to thereby control a temperature of the heater. The temperature control part is configured to set a first target impedance as the target impedance while performing application voltage control for air-fuel ratio detection, and set a second target impedance as the target impedance while performing application voltage control for SOx detection.

A pressure detection signal processing device, engine control system, and non-transitory computer readable medium storing a program are provided. A current-voltage conversion part that converts a current signal corresponding to charge generated by a piezoelectric element in accordance with received pressure into a voltage signal, and digital signal processing parts that perform correction for removing a drift caused by a leakage current of the piezoelectric element on the voltage signal through digital signal processing are provided. The digital signal processing parts include a differentiation processing part that performs differentiation processing on the voltage signal, an integration processing part that performs integration processing on the signal having been subjected to the differentiation processing, and an integration processing part that further performs integration processing on the signal having been subjected to the integration processing.

A vehicle system includes an engine defining a plurality of cylinders and configured to combust a fuel. A method of increasing efficiency of an engine includes controlling an amount of fuel being injected into the plurality of cylinders of the engine via a respective fuel injector. An exhaust gas recirculation (EGR) system is in selective fluid communication with a second subset of the plurality of cylinders and the air intake system to route the second exhaust product from the second subset of the plurality of cylinders to an air intake system. A valve is coupled to the EGR system and the exhaust system. A first sensor is disposed between the valve and the air intake system, and measures an amount of reformate in the second exhaust product when the valve is in a second position.

A failure detection apparatus for a gas sensor includes an electronic control unit configured to: perform control so that a predetermined voltage, which is a positive voltage and is a voltage lower than a limiting current range when the gas sensor does not fail, is applied between a pair of electrodes; acquire a determination current, which is a current flowing between the pair of electrodes when the predetermined voltage is applied between the pair of electrodes; and determine whether the gas sensor fails based on the acquired determination current.

A control apparatus for an engine includes an engine, a state quantity setting device, a spark plug, and a controller. The spark plug ignites air-fuel mixture at predetermined ignition timing so that unburned air-fuel mixture combusts by autoignition after start of combustion of the air-fuel mixture by the ignition, and the controller adjusts a heat amount ratio in accordance with an operation state of the engine through change of the ignition timing, the heat amount ratio representing an index associated with a ratio of an amount of heat generated when the air-fuel mixture combusts by flame propagation with respect to a total amount of heat generated when the air-fuel mixture combusts in the combustion chamber.

A method, control system, and propulsion system use model predictive control to control and track several parameters for improved performance of the propulsion system. Numerous sets of possible command values for a set of controlled variables are determined. Initial constraints for the controlled variables are determined, which include upper and lower limits for each controlled variable and upper and lower rate-of-change limits for each controlled variable. A set of consolidated constraint limits for the controlled variables is then determined. Each consolidated constraint limit is determined by consolidating one of the upper and lower limits with one of the upper and lower rate-of-change limits. A cost for each set of possible command values is determined, and the set of possible command values that has the lowest cost and falls within the set of consolidated constraint limits is selected for use in controlling the propulsion system.

Methods and systems are provided for adjusting a throttle based on an intake oxygen sensor output. In one example, a method may include adjusting a position of a throttle based on a dilution threshold and a total aircharge dilution level, the total dilution aircharge level based on an output of an intake oxygen sensor. Additionally, spark timing may be adjusted based on the total aircharge dilution level.

Systems and methods for diagnosing operation of a sensor of an exhaust system are presented. In one example, the systems and methods may diagnose operation of the sensor when an engine is combusting air and fuel. Further, operation of the sensor may be diagnosed when the engine is not combusting air and fuel so that vehicle occupants may not be disturbed by the diagnostic.

A method of analyzing fuel component using an RF (Radio Frequency) sensor for a vehicle includes: receiving a new fuel into a fuel tank so as to mix existing fuel in the fuel tank with the new fuel, measuring a resonance frequency of the mixed fuel using an RF sensor, comparing the measured resonance frequency of the mixed fuel with a resonance frequency of a standard fuel, determining whether the mixed fuel is a normal fuel through the comparison, maintaining an engine combustion pattern corresponding to the standard fuel when the mixed fuel is a normal fuel, and operating reflecting an engine combustion control.