Hybrid vehicle

A hybrid vehicle comprising:

• an internal combustion engine including:
• an in-cylinder fuel injection valve to allow direct fuel injection in a combustion chamber, and a crank ventilation system;
• a motor;
• a power transmission mechanism connecting a drive shaft of the vehicle and the engine to allow torque transmission therebetween and connecting the drive shaft and the motor to allow torque transmission therebetween;
• and
• a control device having a configuration:
• to control output torque of the engine and output torque of the motor so as to exert an equal torque to a user requiring torque on the drive shaft, the user requiring torque being a torque required on the drive shaft and determined depending on an acceleration control amount by the user, and
• to stop the engine upon a predetermined engine stop condition being satisfied and start the engine upon a predetermined engine start condition being satisfied, the engine stop condition including a condition of a coolant water temperature of the engine being equal to or higher than a intermittency allowance temperature,
• the control device further having a configuration:
• to estimate a mixed fuel amount, the mixed fuel amount being an amount of fuel mixed in lubrication oil of the engine,
• to set the intermittency allowance temperature to rise with increasing amount of the estimated mixed fuel amount,
• to calculate an increased amount of fuel in such a manner that the increased amount is increased as temperature of the coolant water decreases, and increase an amount of fuel injected from the in-cylinder fuel injection valve as the increased amount increases, and wherein
• the control device calculates the estimated mixed fuel amount in such a manner that the estimated mixed fuel amount is increased when the engine is being driven, the coolant water temperature is lower than a first threshold coolant water temperature, and the increased amount of fuel is equal to or larger than a predetermined threshold increased amount.