Method and system for oil dilution control
AssigneeFord Global Technologies, LLC
InventorsTed Haladyna, Douglas Raymond Martin, Paul Stephen Bryan
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for operating an engine in a hybrid vehicle in response to fuel and water dilution of engine lubricating oil. An engine oil dilution counter may be adjusted based on a number of engine hot starts and duration of engine operation above a threshold temperature. In addition, the counter may be adjusted if the engine is started to deplete stale fuel in the fuel tank.
Claims21
A method for an engine in a hybrid vehicle, comprising:
- in response to oil dilution being higher than a threshold while a battery state of charge is higher than a threshold charge, operating an engine to raise engine temperature above a threshold temperature for a duration, wherein one or more of the duration and the threshold temperature is adjusted based on a stale fuel clean-out history.
A method for an engine coupled in a hybrid vehicle, comprising:
- during a first condition, when engine oil dilution is higher than a threshold dilution and while a battery state of charge is higher than a threshold charge, starting the engine to raise an engine temperature above a threshold temperature;
- during a second condition, when a fuel age is higher than a threshold age and while the battery state of charge is higher than the threshold charge, starting the engine to deplete fuel in a fuel tank;
- during both the first and second condition, updating each of the engine oil dilution and the fuel age responsive to the starting the engine;
- and
- during a third condition, when the battery state of charge is lower than the threshold charge, starting the engine to charge the battery.
A method for an engine coupled to a hybrid vehicle, comprising:
- during a first mode of vehicle operation, when fuel age is lower than a threshold age, starting the engine responsive to an oil dilution being higher than a threshold dilution and decrementing each of the fuel age and the oil dilution responsive to the engine starting;
- and
- during a second mode of vehicle operation, when oil dilution is lower than the threshold dilution, starting the engine responsive to the fuel age being higher than the threshold age and decrementing each of the fuel age and the oil dilution responsive to the engine starting.
A method for a hybrid vehicle, comprising:
- during a vehicle drive cycle,
- monitoring each of an engine oil dilution and a fuel age;
- starting an engine responsive to one of the oil dilution being higher than a threshold dilution and the fuel age being higher than a threshold age;
- selectively updating only an oil dilution monitor based on an oil change interval;
- selectively updating only a fuel age monitor based on a fuel tank refill;
- updating each of the oil dilution monitor and the fuel age monitor responsive to the engine starting;
- and
- further updating each of the oil dilution monitor and the fuel age monitor based on a number of engine cold starts over the vehicle drive cycle.
A method for an engine in a hybrid vehicle, comprising:
- during a vehicle drive cycle, in response to oil dilution being higher than a threshold, operating an engine to raise engine temperature above a threshold temperature for a duration, wherein said engine operation with raised temperature is further adjusted based on an age of fuel stored in a fuel tank and prior engine operation over the drive cycle responsive to the age of the fuel.
Dependencies are inferred from the claim text.