Why Does Braking Performance Deteriorate When the Car's Air Conditioning is On?

[SanKhloe]

When the car's air conditioning is turned on, the braking performance deteriorates due to the following reasons: Maximum vacuum in the intake manifold when the air conditioning is off: Normally, when the brake pedal is pressed, the accelerator pedal is released. At this point, the engine speed remains relatively high due to the vehicle's inertia, while the throttle is nearly closed. As a result, the vacuum in the intake manifold is at its maximum, providing the best braking effect. Reduced vacuum in the intake manifold when the air conditioning is on: When the air conditioning is turned on, the engine load increases. To prevent a decline in the vehicle's power performance, the engine control system is usually equipped with an air conditioning idle speed boost device. Under these circumstances, the intake manifold behind the throttle cannot maintain the normal vacuum level, leading to a corresponding deterioration in braking performance.