What are the disadvantages of keeping the vehicle running for a long time without turning it off?

[Eugenia]

The disadvantages of keeping the vehicle running for a long time without turning it off: 1. The engine is in an idle state, and the throttle opening is very small, which will cause the air content in the combustible mixture to be very low, leading to incomplete combustion of the engine and causing carbon deposits; 2. If the vehicle is parked for a long time without turning off the engine, the incomplete combustion of the combustible mixture will increase the burden on the three-way catalytic converter and damage it; 3. Incomplete combustion affects the excessive pollutants in the exhaust gas, harming the environment. Carbon deposits in the engine are very harmful to the engine. If carbon deposits occur in the intake tract, it will affect the airflow speed, increase the intake resistance, and affect the engine's air intake. Some direct-injection engines are also prone to carbon deposits on the piston top. Carbon deposits on the piston top will increase the engine's compression ratio, and the increased compression ratio will raise the likelihood of knocking, which can severely damage the engine.