Should You Turn Off the Engine When Waiting for Someone for a Long Time?

[DeBrynlee]

If you're waiting in the car for someone for less than five minutes, you don't need to turn off the engine. However, if the wait exceeds five minutes, it's advisable to turn off the engine. Prolonged idling can harm the engine, especially in underground parking lots where extended idling is particularly detrimental. The hazards of long-term idling while waiting include: 1. Carbon buildup: Extended idling causes the engine temperature to remain too low, leading to incomplete fuel combustion, which can result in carbon deposits that clog fuel injectors. Severe carbon buildup can cause piston rings to seize or even break. 2. Increased wear: During prolonged idling, poor fuel atomization causes unburned atomized diesel to wash down cylinder walls and mix with lubricating oil, diluting and degrading the oil. This leads to inadequate lubrication of engine components, accelerating wear. 3. Safety risks: Engines running at idle for extended periods experience poor combustion, worsening exhaust emissions. If toxic gases enter the cabin, they can pose life-threatening risks to occupants.