Question

Why do I hear so many people’s ignition starting at stoplights? Are these people turning their car off every time there's a red light?

Answer 1

The phenomenon you are observing is likely due to the increasing popularity of a fuel-saving technique called "stop-start" or "idle-stop" technology in modern cars. Many newer vehicles are equipped with this feature, which automatically shuts off the engine when the car comes to a complete stop, such as at a stoplight or in heavy traffic. When the driver releases the brake pedal or engages the clutch (in manual transmission cars), the engine restarts, allowing the car to move again.

The main purpose of stop-start technology is to reduce fuel consumption and emissions, especially in urban driving conditions where cars often spend a significant amount of time idling at stoplights or in traffic congestion. By turning off the engine when it's not needed, the car consumes less fuel and emits fewer pollutants.

There are several benefits to this technology:

1. Fuel Efficiency: Idling at stoplights or in traffic wastes fuel. With stop-start technology, fuel consumption is reduced, leading to improved fuel efficiency and potentially cost savings for drivers.

2. Environmental Impact: Less fuel consumption means lower carbon dioxide emissions and reduced impact on the environment.

3. Engine Wear Reduction: Frequent engine restarts might sound like it could cause more wear, but modern engines are designed with stop-start technology in mind, and the starter and other components are engineered to handle the increased usage.

4. Noise Reduction: During stops, engines are off, leading to a quieter environment and less noise pollution.

However, not all drivers with stop-start technology choose to use it. Some may disable the feature if they find the frequent engine restarts bothersome, or they might drive older cars that lack this technology entirely.

It's essential to note that not everyone you hear restarting their engines at stoplights necessarily has stop-start technology. Some drivers may turn off their engines manually to save fuel or for other reasons, but this is less common.

In conclusion, the sound of engines starting at stoplights is likely due to the increasing adoption of stop-start technology in modern cars as part of efforts to improve fuel efficiency and reduce emissions.