In a control device for an internal combustion engine and a method of estimating a combustion chamber-wall temperature of an internal combustion engine of the invention, a difference between a wall temperature of the combustion chamber and a cooling water temperature is set according to an integrated value of the intake air amount of the internal combustion engine after start of the fuel-cut, and the estimated value of the wall temperature of the combustion chamber during the fuel-cut is obtained based on the difference and the cooling water temperature.

Methods and systems are provided for calculating a fuel aging of fuel in a fuel tank. In one example, a method may include alerting a vehicle operator and/or adjusting engine operating parameters in response to a fuel aging being greater than a threshold aging.

A supercharging device for an engine is provided, which includes a supercharger provided to an intake passage of the engine, an actuator configured to drive the supercharger, and a controller including a processor configured to control the actuator to drive the supercharger when an operating state of the engine is in a given supercharging range, and to stop the supercharger when the operating state is in a non-supercharging range. The controller estimates an amount of condensate accumulated in an oil pan, and the controller causes the actuator to forcibly drive the supercharger when the estimated amount of condensate is more than a preset amount, even if the operating state is in the non-supercharging range.

An auxiliary chamber having an auxiliary fuel injector is formed on the top surface of a main combustion chamber. When making the air-fuel mixture inside the auxiliary chamber burn, the air-fuel mixture inside the main combustion chamber is burned by jet flames ejected from a communicating hole. After engine startup and until the elapse of a wall surface lower temperature period where the wall surface temperature of the auxiliary chamber becomes a lower temperature than the wall surface temperature of the auxiliary chamber at the time of completion of warmup, an injection ratio of an injection amount of liquid fuel from the auxiliary fuel injector to a fuel injection amount from a main fuel injector is made to decrease compared with after completion of warmup.

Disclosed is a method, system, vehicle, and computer program for improving heat release evaluation at a reciprocating combustion engine. The method comprises providing a model regarding volume deviations in the combustion chamber based on a first set of dynamic parameters of the combustion engine. Said model comprises volume deviations due to thermal changes, due to mass forces and due to pressure forces. The method comprises determining the first set of dynamic parameters relating to the combustion engine, and determining the volume deviation in the combustion chamber based on said provided model and based on said first set of determined dynamic parameters. The method comprises providing an adaption model for the combustion engine based on said determined volume deviation in the combustion chamber, and adapting the combustion engine control and/or a diagnostic system of the combustion engine based on said adaption model so that said heat release evaluation is improved.

Methods and systems are provided for adjusting an ignition timing of an internal combustion engine responsive to a biasing force of a pressure-reactive piston. In one example, an engine may include a pressure-reactive piston having a top wall biased away from a piston base by a pressure of gas contained within the base. An ignition timing of a combustion chamber including the piston is adjusted responsive to an estimated biasing force of the gas against the top wall.

An apparatus includes an engine friction module in operative communication with an engine and structured to interpret engine operation data indicative of an engine friction amount, and a stop/start module structured to compare the engine operation data with predetermined protective criteria that includes an engine friction threshold and to turn off the engine for at least a portion of time based on the engine friction threshold exceeding the engine friction amount.

A boosted engine is provided, which includes an engine body formed with a combustion chamber, a spark plug, a fuel injection valve, a booster, a boost controller, and a control unit including an operating range determining module and a compression end temperature estimating module. In a high load range, the fuel injection valve and the spark plug are controlled so that a mixture gas inside the combustion chamber starts combustion through flame propagation by ignition of the spark plug, and unburned mixture gas then combusts by compression ignition, and the boost controller is controlled to bring the booster into a boosting state. When a gas temperature inside the combustion chamber exceeds a given temperature at CTDC, the fuel injection valve is controlled so that a fuel injection end timing occurs on a compression stroke, and the spark plug is controlled so that the mixture gas is ignited after CTDC.

Various embodiments include a method for controlling an internal combustion engine comprising: determining a speed of the internal combustion engine; determining a cylinder wall temperature of a combustion cylinder of the internal combustion engine; selecting an injection mode based at least in part on the speed and the cylinder wall temperature; and actuating a fuel injector associated with the combustion cylinder based on the selected injection mode.

An internal combustion engine includes a method for operating including, determining, using an accelerator pedal position sensor, an operator request for power and determining an engine operating point based upon the operator request for power. A motored-cylinder temperature is determined based upon the engine operating point, and a knock-limited combustion phasing point is determined based upon the motored-cylinder temperature and the engine operating point. Engine operating parameters associated with achieving the knock-limited combustion phasing point are selected. Operation includes controlling, by a controller, engine control states in response to the engine operating parameters associated with achieving the knock-limited combustion phasing point and the operator request for power.