| 摘要 |
PROBLEM TO BE SOLVED: To attempt to enhance efficiency of the entire vehicle upon a request for warming up an engine.SOLUTION: When boiling evading lower limit flux Qw1 as lower limit flux of coolant required for evading boiling of the coolant in the engine upon a request for warming up the engine is greater than EGR allowable upper limit flux Qw2 as upper limit flux of the coolant in which a temperature of the coolant is equal to or more than a lower limit temperature which allows exhaust gas recirculate combustion (EGR) by an EGR system (S130), the boiling evading lower limit flux Qw1 is set to target flux Qw* (S140), when the boiling evading lower limit flux Qw1 is equal to or less than the EGR allowable upper limit flux Qw2, the target flux Qw* is set so as to make best thermal efficiency &eegr; of the engine within a range from the boiling evading lower limit flux Qw1 to the EGR allowable upper limit flux Qw2 by use of the relationship of flux Qw and the thermal efficiency &eegr; (S150 to S170), and a motor pump is controlled so that the flux of the coolant is the target flux Qw* (S180). |
