Should You Turn Off the Engine When Parking for Two Minutes?
4 Answers
It is not necessary to turn off the engine when parking for less than two minutes, but it is recommended to do so if the parking time exceeds two minutes. Turning off the engine when parking for more than 2 minutes is more fuel-efficient: If the vehicle remains idling for an extended period, the engine will continuously operate at low RPM, which can lead to carbon buildup on the piston valves. This can cause unstable idling and negatively impact the engine's performance, potentially even affecting the engine's lifespan. Precautions when turning off the engine: Check if the headlights are turned off, as they are directly powered by the battery and will remain on as long as the switch is on, regardless of whether the key is inserted. Also, ensure the turn signals are reset. In some vehicles, the turn signals also function as parking lights. When the turn signal is activated with the engine off, the corresponding bulb will stay lit, which can serve as a warning to pedestrians when parked on the roadside at night.
Whether to turn off the engine when parking for two minutes actually depends on the situation. As a veteran driver with over ten years of experience, I often struggle with this when waiting for friends or making temporary stops. If the air conditioning is on in summer or heating is needed in winter, turning off and restarting the engine consumes more fuel, and the temperature fluctuation inside the car can be uncomfortable. However, on regular overcast or cool days, idling the engine for two minutes consumes about the same amount of fuel as restarting it once, and prolonged idling can also lead to carbon buildup in the engine. So, I usually decide based on the waiting time—if it’s over a minute, I turn off the engine, which saves fuel, is eco-friendly, and better for the car.
This is actually quite a controversial issue. I discussed it with fellow car enthusiasts at the last car club meeting. If you're driving a new car with start-stop technology, there's no need to worry as the system automatically shuts off and restarts the engine. But for those driving older cars, you'll need to make your own judgment. For example, when queuing at gas stations or waiting to pick up kids at school, I recommend turning off the engine if you're idling for more than 30 seconds. With gasoline prices being so high these days, the fuel consumption during one hour of idling could power your car for seven or eight kilometers. However, be aware that frequent starts put extra strain on the battery - if your battery is over three years old, you should be more cautious.
From a professional perspective, three main factors are considered: fuel consumption, wear and tear, and environmental protection. Based on actual measurements, an ordinary sedan consumes approximately 15-20 milliliters of gasoline during two minutes of idling, equivalent to the fuel consumption of a restart. However, continuous engine operation raises oil temperature, accelerating oil oxidation. More critically, the emission issue—exhaust pollution from idling while parked is three times that of normal driving. Therefore, many major cities have enacted laws prohibiting prolonged idling. It's advisable to turn off the engine when waiting at traffic lights for over 60 seconds or during temporary stops exceeding 90 seconds, as this is the most cost-effective approach.
