Systems, apparatuses, and methods of controlling an ignitor are disclosed. A method includes: receiving, by a controller, fuel quality data regarding a fuel for a spark-ignition engine; determining, by the controller, a fuel quality metric based on the fuel quality data; and controlling, by the controller, an ignition energy characteristic of an ignitor in response to the fuel quality metric.

Systems and methods for providing spark to an engine are described. In one example, engine knock limited spark timing is expressed as a straight line that is determined in response to engine knock, spark timing, and engine load. The method and system described herein may be performed without extensive engine calibration and mapping.

An engine diagnostic system is provided for diagnosing a deterioration degree of an engine mounted on a vehicle. The engine diagnostic system learns, as a knock learning value, a maximum advancement amount of an ignition timing that reduces knocking. A database stores time-series data of the knock learning value of the engine for each individual engine. The knock learning value is acquired from each of a plurality of vehicles of the same model. An evaluation process computes an evaluation value indicating the deterioration degree of a designated engine using the time-series data of the knock learning value of each engine stored in the database.

An engine diagnostic system is provided for diagnosing a deterioration degree of an engine mounted on a vehicle. The engine diagnostic system learns, as a knock learning value, a maximum advancement amount of an ignition timing that reduces knocking. A database stores time-series data of the knock learning value of the engine for each individual engine. The knock learning value is acquired from each of a plurality of vehicles of the same model. An evaluation process computes an evaluation value indicating the deterioration degree of a designated engine using the time-series data of the knock learning value of each engine stored in the database.

A system and method to enable electronically controlled internal combustion engines to self-adjust parameters and operate properly on different fuels that have wide ranges of physical and chemical properties. Input from a sensor is utilized that gives a signal indicative of the combustion process. The ECU processes the signal and readjusts the engine operating parameters to achieve its operating goals.

According to one or more embodiments, an internal combustion engine may be operated by a method which includes one or more of passing a first fuel and a second fuel into an engine cylinder to form a fuel mixture, and combusting the fuel mixture with a spark plug to translate a piston housed in the engine cylinder and rotate a crank shaft coupled to the piston. The first fuel may comprise a greater octane rating than the second fuel. A target CA50 may correspond to a minimum in specific fuel consumption of the fuel mixture. The spark plug may initiate combustion at a time such that the internal combustion engine operates with an operational CA50 that is within 20 degrees of the target CA50.

According to one or more embodiments, an internal combustion engine may be operated by a method which includes one or more of injecting a first fuel and a second fuel into an engine cylinder to form a fuel mixture, and combusting the fuel mixture with a spark plug to translate a piston housed in the engine cylinder and rotate a crank shaft coupled to the piston. The first fuel may comprise a greater octane rating than the second fuel. A target CA50 may correspond to a minimum in specific fuel consumption of the fuel mixture. The spark plug may initiate combustion at a time such that the internal combustion engine operates with an operational CA50 that is within 20 degrees of the target CA50.

A control apparatus configured to control a power unit of a vehicle includes an electronic control unit configured to i) store a set of measurement values of at least one physical parameter representing a plurality of conditions of the power unit; ii) approximate the stored set of the measurement values, by mixed probability distribution, so as to obtain a first probability distribution of the measurement values representing a first condition, and a second probability distribution of the measurement values representing a second condition; iii) set a discrimination boundary between values representing the first condition and values representing the second condition, between mean values of the first probability distribution and the second probability distribution; and iv) control the power unit, according to a result of comparison between a measurement value and the discrimination boundary.

A method and system for operating an engine includes operating the engine with a first plurality of parameters associated with a first fuel type, comparing a detonation signal a first to a first voltage threshold, forming a plurality of vectors by storing detonation signal values that exceed the first voltage threshold, in vectors as vector values wherein later in time vectors include previous vector values, summing vector values for each vector to form a plurality of sum values and when one of the plurality of sums values exceeds a sum threshold, changing an engine controller to operate with a second plurality of parameters associated with a second fuel type.

A control device of an internal combustion engine is provided. In the case where a switch request for switching from all-cylinder operation to partial-cylinder operation is made, before a switch from the all-cylinder operation to the partial-cylinder operation is executed, an intake air amount increase control increasing an intake air flow rate of an engine by increasing an opening degree of a throttle valve is performed, an ignition timing retardation control retarding an ignition timing is performed, and based on a retardation limit value of the ignition timing at a time point when the switch request is made, a start timing of the intake air amount increase control is changed. As a retardable amount being a difference between an initial ignition timing and the retardation limit value decreases, the start timing of the intake air amount increase control is delayed further.