Does idling with the air conditioning on affect the engine?

[DeMadelyn]

Running the air conditioning while the car is idling has a slight impact on the engine, as it can lead to carbon buildup, particularly around the exhaust pipe tailpipe, and increases fuel consumption. Although idling with the air conditioning on does not cause significant harm to the car, it is advisable to minimize such situations. Precautions for using the car air conditioning: 1. Do not turn on the air conditioning immediately after starting the car: First, open the doors and windows, activate the external circulation to release the accumulated hot air inside the car. Once the interior and exterior temperatures are similar, close the doors and windows, turn on the air conditioning, and switch to internal circulation. This not only lubricates the engine but also improves the cooling efficiency of the air conditioning. 2. Avoid using the air conditioning during prolonged traffic jams or waiting: If the air conditioning is left on during extended periods of idling, the engine remains in an idle state, which places a heavy burden on it. Additionally, incomplete combustion of gasoline at idle produces high concentrations of carbon monoxide. If the surrounding air circulation is poor (e.g., in a garage), the carbon monoxide from the exhaust can enter the car, posing a risk of poisoning to the occupants. 3. Do not set the temperature too low: The ideal temperature for the car air conditioning is around 25°C. If there are elderly or children in the car, it is best not to set it below 27°C. Also, consider the external temperature: the difference between the interior and exterior temperatures should generally not exceed 5–6°C. 4. Do not keep the internal circulation on continuously: When first turning on the air conditioning, it is best to use external circulation. After the temperature has dropped, switch to internal circulation, and periodically alternate between internal and external circulation. 5. Avoid direct airflow from the vents: When using the cold air setting, direct the airflow upward to promote convection between the hot and cold air inside the car. This helps cool the car more quickly and enhances comfort for the occupants.