An engine includes a low-pressure delivery pipe that stores fuel to be injected from port injection valves, a feed pump that supplies the fuel to the low-pressure delivery pipe, a high-pressure delivery pipe that stores the fuel to be injected from in-cylinder injection valves, a high-pressure pump driven in response to rotation of the engine, and a fuel pressure sensor that detects a pressure of the fuel stored in the low-pressure delivery pipe. An engine ECU controls the feed pump based on a detection value from a fuel pressure sensor, and when the engine ECU executes an abnormality diagnosis of the fuel pressure sensor, the engine ECU increases a rotational speed of the engine to be higher than a rotational speed when the engine ECU does not execute an abnormality diagnosis of the fuel pressure sensor. This improves the accuracy of an abnormality determination of the fuel pressure sensor.

A soot particulate sensor has a ceramic support made from an aluminum silicate, which is provided with a conductor path made of an intermetallic compound.

An internal combustion engine comprises an exhaust purification catalyst and an air-fuel ratio sensor arranged at a downstream side of the exhaust purification catalyst, stops or decreases a feed of fuel as fuel cut control, and controls an air-fuel ratio of exhaust gas to a rich air-fuel ratio after the end of the fuel cut control as post reset rich control. The diagnosis system calculates a first characteristic of change of air-fuel ratio at the time when the output air-fuel ratio first passes a first air-fuel ratio region leaner than a stoichiometric air-fuel ratio and a second characteristic of change of air-fuel ratio at the time when the output air-fuel ratio first passes a second air-fuel ratio region including a stoichiometric air-fuel ratio. The diagnosis system diagnoses the abnormality of the air-fuel ratio sensor based on the first characteristic of change of air-fuel ratio and the second characteristic of change of air-fuel ratio. As a result, it is possible to suppress the effects of the change of state of the exhaust purification catalyst while accurately diagnosing the abnormality of deterioration of response of a downstream side air-fuel ratio sensor.

Methods and systems are provided for estimating water storage in a charge air cooler (CAC). In one example, an amount of water in charge air exiting the CAC may be based on an output of an oxygen sensor positioned downstream of the CAC. Further, engine actuators may be adjusted to increase combustion stability and/or reduce condensate formation based on the amount of water exiting the CAC.

A method for checking the function of a sensor for detecting soot is provided, the sensor including at least two measuring electrodes situated on a substrate made of an electrically insulating material, and a heating element, the method including: carrying out a first current-voltage measurement at a first temperature to ascertain a first measured variable, carrying out a second current-voltage measurement at a second temperature to ascertain a second measured variable, and forming a difference between the first measured variable and the second measured variable.

Methods for optimizing exhaust gas system regeneration and cleaning are provided. The exhaust gas system can include an exhaust gas stream supplied by an exhaust gas source to a particulate filter device through an exhaust gas conduit, and a gas sensor having a sampling end disposed within the exhaust gas conduit upstream from the particulate filter device. The methods can include detecting a gas sensor malfunction, detecting particulate filter device soot loading, and performing an optimized maintenance utilizing at least one common technique. A common technique is one which is capable of cleaning a gas sensor and regenerating a PF device. The exhaust gas source can comprise an internal combustion engine and the at least one common technique comprises a post-injection strategy. Systems for performing the disclosed methods are also provided.

A valve control device controls a valve drive mechanism on the basis of a degree-of-opening signal for a valve and a startup signal for an engine, and includes: a drive signal generating unit that, when it is determined on the basis of the startup signal that the engine is stated, generates a test drive signal for test-driving the valve before the generation of a normal drive signal associated with normal driving of the valve; and an abnormality determining unit that, on the basis of the degree-of-opening signal during the test driving, determines whether or not an abnormality has occurred in the drive mechanism. The drive signal generating unit stops generating the test drive signal and the normal drive signal when the abnormality determining unit determines that the abnormality has occurred in the drive mechanism.

Methods are provided for identifying degradation in components of a compressor recirculation valve (CRV). One method includes differentiating between degradation of a throttle of the CRV and a position sensor of the CRV based on each of a throttle inlet pressure and commanded position of the throttle of the CRV. The method also includes utilizing output from the position sensor of the CRV in response to the commanded position of the throttle of the CRV.

A method of filtering a targeted frequency from a pedal input signal is provided. The method includes the steps of sampling the pedal input signal at a sampling frequency, calculating a moving average of the pedal input signal from samples of the pedal input signal, and outputting a filtered signal based on the moving average. A throttle filter system is also provided. The system includes a pedal configured to be actuated to set a desired acceleration of a vehicle, a position sensor configured to convert a position of the pedal into an electrical signal, a vehicle driveline configured to accelerate the vehicle, and a filtering module configured to accept the electrical signal from the position sensor and to filter the electrical signal to remove oscillations at a targeted frequency. In the system, the driveline accelerates the vehicle based on the filtered electrical signal.

An apparatus for controlling an oxygen sensor may include an oxygen sensor configured to measure the exhaust gas which is generated by the combustion of the engine to generate an oxygen signal, and a controller configured to detect, through the oxygen sensor, a lag of the oxygen signal having responsiveness which is reduced depending on an oxygen amount of the exhaust gas, store information on occurrence factors which cause the lag of the oxygen signal, and increase a current heating quantity of a corresponding specific region about the occurrence factors to reconfirm whether the oxygen signal lags and determine the oxygen sensor as a failure or release a failure detection for the oxygen sensor.