What are the consequences of leaving the car running for five hours without turning it off?

[SanClayton]

Leaving the vehicle running without turning it off for an extended period can lead to the following consequences: 1. The engine remains in a low-speed operating condition; 2. The pistons and valves are more prone to carbon buildup, which can result in unstable idling and other adverse effects on the engine's power performance, and may even impact the engine's service life. Additional information: The three-way catalytic converter may not reach its operating temperature, which can affect its lifespan. Most vehicle models are equipped with a three-way catalytic converter in the exhaust system. This is the most important external purification device for vehicle exhaust, converting harmful gases such as CO, HC, and NOx emitted from the exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction. Prolonged idling with the air conditioning on makes it difficult for the three-way catalytic converter to reach the appropriate operating temperature, reducing its exhaust treatment capability and negatively affecting its lifespan.