Stop and restart device for vehicular engine

摘要

An automatic engine stop and restart device for a vehicle provided with a brake booster using an intake negative pressure generated by the engine rotation as the boost source, is provided with a sensor for detecting the negative pressure of the brake booster. The engine is restarted (steps 180 and 190) when the negative pressure decreases to a predetermined value or less during engine stop. Sufficient surge tank negative pressure, that is, the brake booster negative pressure, is secured by restarting of the engine. This prevents the deterioration of the brake booster function resulting from increased engine stop frequency.