What are the hazards of running the air conditioning while idling without turning off the engine?

[VanJuliet]

Running the air conditioning while idling without turning off the engine can lead to carbon buildup in the car's engine and may even pose life-threatening risks. Here are the specific details: Causes engine carbon buildup: When the engine is idling, the throttle is in a critically closed state, resulting in minimal air intake. At this time, the engine operates in a rich fuel injection mode, and due to the overly rich air-fuel mixture, carbon deposits tend to accumulate more. If the air conditioning is also running, the engine needs to output additional power to avoid stalling, which typically raises the engine speed by about 50 RPM. This low-speed, load-bearing operation can lead to even more carbon buildup. May pose life-threatening risks: Prolonged idling with the air conditioning on can result in excessive carbon monoxide production due to the overly rich air-fuel mixture and incomplete combustion. Carbon monoxide is slightly lighter than air and can accumulate around the vehicle in windless conditions. This gas may then be drawn back into the air conditioning system, potentially causing oxygen deprivation and suffocation for passengers inside the car, leading to dangerous situations.