Warm-up control apparatus and warm-up control method for internal combustion engine

摘要

A warm-up control apparatus of an internal combustion engine is installed in a vehicle equipped with a brake booster that uses a negative pressure in an intake pipe of the internal combustion engine. The apparatus performs a warm-up control of the engine by retarding the ignition timing and increasing the amount of intake air. If during execution of the warm-up control, the brake pedal is operated, or the accelerator is off while the vehicle is running at or above a predetermined speed, or the decreasing rate of the amount of accelerator operation is greater than or equal to a predetermined value while the vehicle is running at or above a predetermined speed, the control apparatus recovers the intake pipe negative pressure by reducing the amount of intake air set in relation to the warm-up control.