Engine operation for plug-in hybrid electric vehicle

摘要

A method, comprising propelling a vehicle with an engine and a motor starting the engine if energy stored in an energy storage device is greater than an upper threshold level when a contaminant amount in the engine oil is greater than a threshold amount. In this way, it is possible to harmonize fuel degradation along with oil degradation, while still providing efficient vehicle and engine operation.

主权项

1. A method, comprising:
propelling a vehicle with an engine and a motor; a first and second charge threshold, the first charge threshold greater than the second charge threshold, and starting the engine if energy stored in an energy storage device is greater than the first charge threshold when a contaminant amount in engine oil is greater than a contaminant threshold amount, wherein the contaminant amount is determined based on a number of counted engine starts where engine temperature is less than a temperature threshold, engine stops where engine temperature is less than the temperature threshold, and engine on time.