If you mean the claim “turn on your headlights for 10 seconds before driving to save money,” that’s generally not a real fuel-saving technique.
- Headlights use electricity, which ultimately comes from the alternator and engine in a gasoline/diesel car. Turning them on adds a small load rather than saving fuel.
- 10 seconds of headlights before driving is unlikely to produce any meaningful savings.
- If someone recommends it because they believe the battery or engine needs to “warm up” electrically, that’s a misconception.
- Modern cars generally don’t need a long warm-up while idling. After starting, wait briefly for the engine to stabilize, then drive gently until it reaches operating temperature.
- For saving money, bigger factors are smooth acceleration, avoiding excessive idling, maintaining proper tire pressure, keeping up with maintenance, and avoiding unnecessary weight.
- If you’re talking about cold weather, headlights still don’t need to be turned on for 10 seconds as a fuel-saving measure. In very cold conditions, following your vehicle manufacturer’s starting procedure is more useful.
If you saw this as a specific “10-second trick” on TikTok, YouTube, or somewhere else, send me the exact claim and I can explain whether that particular technique is legitimate.