Engine with engine oil viscosity control and method for controlling the same

An engine oil system for an internal combustion engine having varying engine operating parameters, the engine oil system comprising:

• an electronic control module which contains a memory having predetermined target engine oil viscosity settings which target oil viscosities vary over time based on engine operating parameters;
• an oil viscosity sensor disposed in communication with the electronic control module and which generates an output indicative of the actual viscosity of the oil within the engine;
• an engine oil cooler;
• an oil cooler flow control valve disposed in communication with the electronic control module, the oil cooler flow control valve being moveable between an open and closed position to regulate coolant flow to the engine oil cooler based upon an output of the electronic control module;
• and
• the electronic control module programmed to:
• compare the output of the engine oil viscosity sensor with the varying target oil viscosity generated by the electronic control module;
• generate an output that causes the oil cooler flow control valve to move towards the closed position during those times when the output of the engine oil viscosity sensor exceeds the target oil viscosity, thereby increasing the temperature of the coolant within the engine oil cooler and, in turn, lowering the viscosity of the engine oil within the engine oil system to lower the actual oil viscosity toward the target oil viscosity;
• and
• generate an output that causes the oil cooler flow control valve to move towards the open position during those times when the output of the engine oil viscosity sensor is below the target oil viscosity, thereby decreasing the temperature of the coolant within the engine oil cooler and, in turn, raising the viscosity of the engine oil within the engine oil system to raise the actual oil viscosity toward the target oil viscosity.