An engine cooling system for increasing and controlling a wall temperature of a cylinder head is provided. The cooling system includes a radiator passage that passes through a radiator, a radiator-bypass passage that bypasses the radiator, a first fluid temperature sensor that acquires a fluid temperature of an engine coolant flowing through a bore passage for cooling a cylinder, a second fluid temperature sensor that acquires the fluid temperature of the engine coolant flowing through a head passage for cooling a cylinder head, a thermostat valve arranged in the radiator passage, a flow rate regulator valve arranged in the radiator-bypass passage, and an electronic control unit (ECU). While controlling the thermostat valve on the basis of a detection result of the first fluid temperature sensor, the ECU controls the flow rate regulator valve on the basis of a detection result of the second fluid temperature sensor.

A coolant temperature sensor abnormality determination device includes a determination unit configured to determine whether or not two coolant temperature sensors, which are configured to detect the temperature of the coolant, have an abnormality. The determination unit has a determination permission condition under which a reference temperature is set to an estimated temperature of a present time point and the estimated temperature is then changed from the reference temperature by a determination temperature. The determination unit is configured to determine, when the determination permission condition is satisfied, that the two coolant temperature sensors are functioning normally if a discrepancy between detection values of the two coolant temperature sensors is less than a normal temperature that is less than or equal to the determination temperature.

A failure diagnosis method of a coolant temperature sensor for a vehicle, may include determining, by a controller, whether or not it is in a flow stop state that stagnates the flow of coolant by a flow control valve; obtaining, by the controller, an engine outlet coolant model temperature when it is in the flow stop state; and diagnosing, by the controller, as a failure of an engine outlet-side outlet water temperature sensor when the coolant model temperature is equal to or greater than a reference temperature and the flow stop state is maintained by the flow control valve.

A method can include: acquiring, via one or more sensors disposed in a vehicle, one or more engine operation parameters relating to operation of an internal combustion engine disposed along a coolant flow path in the vehicle; calculating at least one target coolant temperature according to the one or more engine operation parameters; and controlling a valve actuator to regulate flow of a coolant through the coolant flow path via an electric coolant valve operatively coupled to the valve actuator such that a temperature of the coolant changes in accordance with the at least one target coolant temperature.

Methods and systems are provided for an internal combustion engine assembly comprising a water pump driven by a crankcase venting system. In one example, a method may include adjusting a transmission ratio of a magnetic transmission in response to a temperature of an engine, wherein the magnetic transmission connects a water pump to a crankcase venting system of the engine.

A cooling system includes an electric pump, a cooling target temperature sensor, a coolant temperature sensor, and an electronic control unit. The electric pump pumps a coolant to a circulation channel connected to an inlet and an outlet of a cooling channel in which heat is exchanged with a cooling target. The cooling target temperature sensor detects a cooling target temperature. The coolant temperature sensor is arranged upstream of the inlet in the circulation channel, and detects a coolant temperature. The electronic control unit controls driving of the electric pump so that a discharge flow rate of the electric pump matches a target flow rate, and sets the target flow rate using an equation based on a reference value obtained by dividing a difference between the cooling target temperature and a target cooling temperature of the cooling target by a difference between the cooling target temperature and the coolant temperature.

A heat accumulation and dissipation device (1) for an internal combustion engine (2) includes, in a cooling circuit (3) for circulating cooling water used to cool the internal combustion engine (2), a heat accumulator (7) for accumulating the cooling water, and an exhaust heat recovery device (9) for recovering the heat of exhaust gas through the cooling water, wherein when the internal combustion engine (2) is started, heat is dissipated by sending the cooling water of the heat accumulator (7) to the internal combustion engine (2). The cooling circuit (3) includes a heat accumulation and dissipation circuit (8) configured to perform heat accumulation and dissipation while circulating the cooling water between the internal combustion engine (2) and the heat accumulator (7), and the heat accumulator (9) is arranged upstream of the heat accumulator (7) of the heat accumulation and dissipation circuit (8).

A generator set is disclosed. The generator set may include a liquid-cooled engine and an alternating current (AC) generator coupled to the liquid-cooled engine. The generator set may include an AC fan associated with the liquid-cooled engine and connected to the AC generator via a relay and an engine control module (ECM) associated with the liquid-cooled engine and connected to the AC fan via the relay. The generator set may include an engine temperature sensor associated with the liquid-cooled engine and connected to the ECM via a first circuit and an engine air temperature sensor associated with the liquid-cooled engine and connected to the ECM via a second circuit.

An air conditioner for a vehicle including an engine, which serves as a power source and is configured to allow a cooling water to flow therethrough, includes a cooling water circuit, a heater, temperature sensors, and an output controller. The cooling water circuit allows the cooling water to circulate therein in a heating operation. The heater serves as a heat source, other than the engine, configured to heat the cooling water circulating in the cooling water circuit. The temperature sensors are connectable to the cooling water circuit and are configured to detect a temperature of the cooling water. The temperature sensors are positioned upstream and downstream of at least one of the engine and the heater. The output controller is configured to adjust at least an output of the heater based on the temperatures of the cooling water detected by the temperature sensors.

A thermostat for an engine cooling system is arranged between an engine and a radiator. The thermostat may include: a housing having a coolant inlet through which inflow coolant flows in from the engine and a radiator side outlet; a main valve provided in the housing and coupled to one side of a wax to open and close the radiator side outlet by a change in volume of the wax; and a heating unit coupled to the other side of the wax to supply heat to the wax.