As the name implies, automatic stop/start shuts off the engine instead of it idling at a stop and then rapidly restarts the engine when you want to drive away. ... If you do a lot of stop-and-go driving, you're reducing emissions and saving fuel by not idling for extended periods.

Is auto stop bad for your car?

In short, stop-start systems can help you save fuel, and they won't damage your engine. So, unless you can't stand the restarts, it's worth keeping it on.

Does auto stop really save gas?

Most people think the amount of fuel saved using a start-stop system is negligible, but in reality, that fuel burned while idling at a stop adds up quickly. A study by the Society of Automotive Engineers found that using start-stop can see a car's fuel economy improve by over eight percent in heavy traffic.