An in-cylinder pressure sensor system and a pressure sensor adaptor that allows for the inclusion of a pressure sensor to monitor the pressure of an engine cylinder is provided. The pressure sensor adaptor includes a first end, a second end, a threaded section, a cylindrical midsection, and an annular section; and a pressure sensor channel that comprises an opening in the first end and an opening in a second end and spans from the first end to the second end through the threaded section, the cylindrical midsection, and the annular section. The pressure sensor may be housed in the pressure sensor channel of the pressure sensor adaptor.

A method of detecting uncontrolled combustion in an internal combustion engine includes sampling in-cylinder pressure sensor configured to measure pressure in a cylinder of the engine and generate a pressure signal, calculating a combustion intensity metric based on the pressure signal, determining a parameter describing how close the engine is to an uncontrolled combustion condition based on the combustion intensity metric, and controlling a substitution rate of a first fuel and a second fuel based on one or more of the parameter and the combustion intensity metric.

In an internal combustion engine in which a plurality of cylinders are arranged in series in a cylinder section, pressures of the cylinders can be detected by a smaller number of pressure sensors. An engine in which a plurality of cylinders are arranged in series in a cylinder section includes a communication path through which combustion chambers of the cylinders adjacent to each other communicate with each other, and a pressure sensor is disposed in the communication path.

Methods and systems are disclosed for operating an engine that includes a knock control system that may determine contributions of individual noise sources to an engine background noise level. The contributions of the individual noise sources may be the basis for establishing the presence or absence of knock in one or more engine cylinders.

An abnormality diagnosis device of an in-cylinder pressure sensor is provided. The device carries out a performance determination in which a performance quality of the sensor is determined based on an electric signal inputted from the sensor. The device carries out a first determination in which the performance determination is performed at a given timing, a performance recovery in which a given deposit removal control is executed in which a deposit accumulating inside the combustion chamber is removed when the performance quality of the in-cylinder pressure sensor is determined to fall below a given reference value, and a second determination in which the performance determination is carried out again after the performance recovery. In the second determination, the in-cylinder pressure sensor is diagnosed as abnormal when the performance quality of the sensor is determined to fall below the given reference value.

A method for operating an internal combustion engine with a motor, having a moving machine part and at least one machine element which retains the moving machine part and is subject to wear, such as, for example, a supporting, sealing, guiding or the like retaining machine element that is subject to wear during operation relative to the moving machine part, which machine element, because of the wear, is service-life-limiting for the operation of the internal combustion engine, whereinfor the operation of the internal combustion engine, a service-life-limiting time interval until the next maintenance of the internal combustion engine is specified, andthe internal combustion engine has a number of service-life-limiting machine elements, wherein for the at least one service-life-limiting machine element a remaining service life is forecast and the service-life-limiting time interval is determined therefrom.

An adaptive, any-fuel reciprocating engine using sensor feedback integration of high-speed optical sensors with real-time control loops to adaptively manage the electronic actuation schemes over a range of engine loads and fuels. The engine uses one or more optical sensors to collect specific types of gas property data via a spectroscopic technique to adaptively control various components within the engine.

A method for predictive maintenance of components of an internal combustion engine by a structure-borne sound sensor includes: recording vibrations of the components of the internal combustion engine by at least one structure-borne sound sensor; and during operation of the internal combustion engine, continuously checking a release for diagnosing a wear condition of the components of the internal combustion engine. The one or more structure-borne sound sensors, which are arranged at one or more positions on the internal combustion engine, record measurement signals and forward them to evaluation electronics. The measurement signals are time-synchronized to a characteristic state of the internal combustion engine or the measurement signal recording is time-triggered. The time-synchronized or triggered measurement signals are decoded into measurement data. The decoded measurement data is subjected to a signal transformation. One or more spectrograms are generated from the signal transformation.

Systems and methods for detecting at least one non-functional combustion chamber of an engine comprising a plurality of combustion chambers are described herein. In response to detecting a partial output power loss of the engine, one of the plurality of combustion chambers is assessed by monitoring an engine parameter indicative of an output power of the engine, determining whether a change in the engine parameter has occurred, when the change has occurred, determining that the combustion chamber is functional, and when no change has occurred, determining that the combustion chamber is non-functional and discontinuing fuel injection to the non-functional combustion chamber.

An internal combustion engine includes a crankcase that defines a crank chamber, a crankshaft that has a crank housed in the crank chamber and is rotatably supported on the crankcase, a cylinder block that is joined to the crankcase and defines a plurality of cylinders in a horizontally-opposed arrangement, a to-be-detected body that rotates integrally with the crankshaft, and a detection sensor that extends through the crankcase from an upper face of the crankcase, is made to face a trajectory of the to-be-detected body, and generates a pulse signal in response to movement of the to-be-detected body. Thus, in a so-called horizontally-opposed internal combustion engine, a structure for disposing a detection sensor that can detect the angular velocity of a crankshaft with high precision is provided.