Does a car consume fuel when idling without turning off the engine?

[McVincent]

Leaving a car idling without turning off the engine will definitely consume fuel. The following are the hazards of idling without turning off the engine: 1. When the engine speed is very low, the intake vortex weakens, resulting in poor fuel atomization and incomplete combustion of the fuel. Additionally, at low engine speeds, valve leakage and piston ring leakage increase. Combined with the extended contact time between the combustion gases and the cylinder walls, heat dissipation losses increase, leading to higher fuel consumption. 2. During idling, the engine oil pressure is relatively low, worsening the lubrication conditions of moving parts. Unburned fuel washes the cylinder walls, and incomplete combustion can easily lead to carbon deposits. These factors accelerate the wear of moving parts. Moreover, when the coolant temperature drops below 60 degrees, combustion byproducts in the cylinders may react chemically with moisture, forming acids that increase cylinder corrosion.