Various embodiments include a method for determining the temperature of an engine oil in an internal combustion engine comprising: acquiring a value of a parameter characterizing a current operating point of the internal combustion engine; and calculating the temperature of the engine oil using an oil temperature model. The oil temperature model depends at least in part on dilution of the engine oil caused by different components in the engine oil and accounts for modified heating behavior of the engine oil based on the dilution.

A device for preventing dilution of engine oil includes an oil pan in which oil for lubrication of the engine is recovered with fuel. An exhaust purifier is provided on a rear end of the engine and purifying exhaust gas. A gas passage can guide flow of exhaust gas passing through the exhaust purifier to the oil pan. A gas valve can control flow rate of the exhaust gas flowing in the gas passage. A controller controls an opening ratio of the gas valve depending on a temperature of oil inside the oil pan to maintain the temperature of the oil equal to or higher than a temperature at which the fuel in the oil pan is vaporized.

A blow-by gas treating device discharges blow-by gas into intake air. A controller selects and executes one of a fuel cutoff process and a fuel introduction process when stopping combustion in a cylinder under a situation in which a crankshaft of the internal combustion engine is rotating. An injection valve controlling section controls a fuel injection valve to regulate a fuel injection amount in a period in which the combustion in the cylinder is stopped under the situation in which the crankshaft is rotating. The injection valve controlling section decreases the fuel injection amount from the fuel injection valve as an oil temperature that is the temperature of engine oil increases.

An estimation device is applicable to a combustion system in which relative movement of a piston to a cylinder is lubricated with a lubricating oil. An estimation device includes a mixing acquisition unit and a piercing force estimation unit. The mixing acquisition unit acquires a mixing ratio of various components contained in a fuel injected into the combustion chamber. The piercing force estimation unit estimates a piercing force of the fuel injected into the combustion chamber according to the mixing ratio acquired with the mixing acquisition unit to manage reach of the fuel, which is injected into the combustion chamber of the internal combustion engine, at least one of the cylinder and the piston.

An engine oil state control device for controlling a fuel mixture ratio of a fuel mixed in an engine oil of an engine on which a predetermined combustion control is performed includes comprising a fuel mixture ratio acquisition part configured to acquire the fuel mixture ratio, and an oil temperature rise control part configured to perform an oil temperature rise control for increasing an evaporation rate of the fuel mixed in the engine oil if the fuel mixture ratio is equal to or greater than a first threshold.

A method for operating a motor vehicle provided with a hybrid drive apparatus. The hybrid drive device is equipped with an internal combustion engine that can be operated with a fuel, as well as with an electric engine, and a lubricant is supplied at least intermittently to the internal combustion engine. At the same time, a lubricant dilution value is determined with a dilution of the lubricant so that the internal combustion engine is started when a first threshold value is exceeded by the lubricant dilution value, and when the motor vehicle is located on a regeneration route of an anticipated driving route of the motor vehicle and the regeneration route is sufficient to reduce the lubricant dilution value by a specified value.

A device for preventing dilution of engine oil includes an oil pan in which oil for lubrication of the engine is recovered with fuel. An exhaust purifier is provided on a rear end of the engine and purifying exhaust gas. A gas passage can guide flow of exhaust gas passing through the exhaust purifier to the oil pan. A gas valve can control flow rate of the exhaust gas flowing in the gas passage. A controller controls an opening ratio of the gas valve depending on a temperature of oil inside the oil pan to maintain the temperature of the oil equal to or higher than a temperature at which the fuel in the oil pan is vaporized.

Various embodiments include a method for determining the temperature of an engine oil in an internal combustion engine comprising: acquiring a value of a parameter characterizing a current operating point of the internal combustion engine; and calculating the temperature of the engine oil using an oil temperature model. The oil temperature model depends at least in part on dilution of the engine oil caused by different components in the engine oil and accounts for modified heating behavior of the engine oil based on the dilution.

A blow-by gas treating device discharges blow-by gas into intake air. A controller selects and executes one of a fuel cutoff process and a fuel introduction process when stopping combustion in a cylinder under a situation in which a crankshaft of the internal combustion engine is rotating. An injection valve controlling section controls a fuel injection valve to regulate a fuel injection amount in a period in which the combustion in the cylinder is stopped under the situation in which the crankshaft is rotating. The injection valve controlling section decreases the fuel injection amount from the fuel injection valve as an oil temperature that is the temperature of engine oil increases.

A positive crankcase ventilation gas diversion and reclamation system comprises a positive crankcase ventilation gas diversion line to divert oil laden positive crankcase ventilation gases from the air intake manifold of an internal combustion engine. A positive crankcase ventilation gas diversion line directs oil laden positive crankcase ventilation gases into a vapor headspace of a fuel tank. A pressure sensor measures a vapor pressure in a vapor headspace of a fuel tank, and a fuel tank vent valve is operative with a fuel tank vent line. A controller actuates the fuel tank vent valve into an open position and discharges fuel enriched vapor to the air intake manifold of the internal combustion engine. A method permits diverting positive crankcase ventilation gasses from the air intake manifold of an engine, and reclaiming oil laden fuel components and/or particulates from positive crankcase ventilation gasses.