To provide a controller and a control method for internal combustion engine which can calculate the shaft torque in unburning with good accuracy in all the operating condition in which calculation is required, using the shaft torque in unburning which was set in the specific operating condition, and can improve estimation accuracy of the parameter relevant to the combustion state. A controller for internal combustion engine calculates a specific shaft torque in unburning with reference to a specific unburning condition data; calculates specific and current generated torques of unburning assumption using the physical model equation; calculates a current shaft torque in unburning based on the specific shaft torque in unburning, and the specific and current generated torques of unburning assumption; and calculates an increment of gas pressure torque by burning based on the current shaft torque in unburning and the actual shaft torque in burning condition.

To provide a controller and a control method for internal combustion engine which can reduce arithmetic load, while suppressing deterioration in the estimation accuracy of the parameter relevant to the combustion state, even if the error component of high frequency is included in the crank angle acceleration. A controller for internal combustion engine, by referring an unburning condition data, calculates a shaft torque in unburning in the vicinity of the top dead center in the burning condition; calculates an external load torque based on calculated shaft torque in unburning and the actual shaft torque in burning in the vicinity of the top dead center; calculates a shaft torque in unburning by referring the unburning condition data; calculates an increment of gas pressure torque by burning based on the shaft torque in unburning, the actual shaft torque in burning, and the external load torque.

Methods and systems are provided for balancing fuel delivery amongst all engine fuel injectors. In one example, a method may include selectively adjusting an injection timing of one or more fuel injectors of a plurality of fuel injectors to increase an inter-injection period between two consecutive fuel injections in response to a request to balance amounts of fuel injected by the plurality of fuel injectors.

In an internal combustion engine control apparatus, an electronic control device is configured to subject a signal from a knock sensor to short-time Fourier transform, to thereby generate an observation matrix. Further, the electronic control device is configured to decompose the observation matrix into knocking vibration data being data on vibration caused by knocking and mechanical vibration data being data on vibration other than the knocking.

An injection control device of capable of correcting an energization time even in an S/N non-guaranteeable situation includes: an energization controller calculating an energization time correction amount based on an area correction performed by an energization time correction amount calculator regarding electric current flowing in a fuel injection valve when the fuel injection valve is electrically driven for injecting fuel; and an energization instruction time calculator correcting an energization instruction time for fuel injection in a next cycle and thereafter by using the energization instruction time correction amounts in or before a current cycle.

A method for controlling an internal combustion engine with a crankshaft position sensor, intake air pressure sensor and fresh air intake throttle valve, includes: determining the engine's rotational speed based on the crankshaft position derivative relative to time; determining the intake air pressure for a first crankshaft position corresponding to 180° before top dead center; determining the intake air pressure for a second crankshaft position corresponding to 390° before top dead center; determining an atmospheric pressure learning pressure threshold based on the engine's rotational speed; determining whether the difference between the intake air pressures for the first and second crankshaft positions is below the atmospheric pressure learning pressure threshold; if so, commanding atmospheric pressure learning by applying a first-order filter to the intake air pressure for the second crankshaft position; and controlling the internal combustion engine as a function of the learned atmospheric pressure value.

A spark ignited internal combustion engine is controlled in response to a self-learned TOB reference. The self-learned TOB reference is based on a difference between a learned TOB offset and a desired or target TOB, and a sensed TOB. The learned TOB offset at a given operating condition, such as charge pressure, can be found by interpolating between the learned charge pressure breakpoints in a TOB learning algorithm. The TOB learning algorithm can include using a filtered charge pressure value to indicate the engine load at which the TOB is learned. An index determination is made with a look up table with charge pressure as an input and an array index of learned charge pressure and learned TOB offset as outputs.

To provide a controller and a control method for internal combustion engine which can reduce arithmetic load, while suppressing deterioration in the estimation accuracy of the parameter relevant to the combustion state, even if the error component of high frequency is included in the crank angle acceleration. A controller for internal combustion engine, by referring an unburning condition data, calculates a shaft torque in unburning in the vicinity of the top dead center in the burning condition; calculates an external load torque based on calculated shaft torque in unburning and the actual shaft torque in burning in the vicinity of the top dead center; calculates a shaft torque in unburning by referring the unburning condition data; calculates an increment of gas pressure torque by burning based on the shaft torque in unburning, the actual shaft torque in burning, and the external load torque.

Systems and methods for determining degradation of a cylinder deactivation mechanism are described. In one example, engine data generated while an engine is operation with all of its cylinders active is used to correct engine data generated while one or more engine cylinders are deactivated to improve detection of a degraded cylinder deactivation mechanism.

In as internal combustion engine control apparatus, an electronic control device is configured to subject a signal from a knock sensor to short-time Fourier transform, to thereby generate an observation matrix. Further, the electronic control device is configured to decompose the observation matrix into knocking vibration data being data on vibration caused by knocking and mechanical vibration data being data on vibration other than the knocking.