Engine control system

摘要

Methods and systems are provided for adjusting the operation of an electric coolant pump in a hybrid vehicle system. During vehicle compression braking conditions, a motor propels the vehicle while the engine spins un-fueled to absorb torque. During such conditions, the coolant pump is operated based on the absorbed torque to maintain an engine temperature within a threshold.

主权项

1. A method, comprising:
during conditions when a hybrid vehicle is propelled by a motor while the hybrid vehicle engine spins un-fueled, and a system battery state of charge is greater than an upper limit,
absorbing compressor braking torque at the engine and not at the battery to maintain vehicle speed at a desired speed while increasing a pump speed of an engine coolant pump as an amount of absorbed torque increases, and increasing a speed of a radiator fan as the pump speed increases to control engine temperature.