Shifting to Neutral at stop lights

I’ve heard that you will improve your gas mileage if you shift into neutral at stop lights. Is this true, and if it is, does it do any damage to the car?

If you have a manual transmission, shift into neutral to save wear on the clutch throwout bearing. If you have an automatic, don’t worry about it. Gas mileage will not be affected either way.

Shift to neutral (or Park) if you are tired of keeping your foot on the brake. Your gas mileage will not be affected one way or the other.

I usually just pull my handbrake up if that’s the case while I keep it in gear

Everybody’s trying to save gas now. It will have no effect except irritate everyone behind you. If you want to save gas, avoid jerky jack rabbit starts, anticipate stop lights and other traffic conditions, easy and steady on the gas, and slow it down a little. In addition to good maintenance.

If you have an auto then the only damage you will do to your car is if you step on the accelerator before shifting into drive otherwise forgetaboutit.

I am not a professional mechanic but I believe shifting to neutral and back to drive does more damage than leaving it in drive. It will not effect gas mileage.

I see the rpm INCREASE in neutral. I leave mine in gear for lower idling rpm.

leave it in gear

I have been told that for one of my cars the engine management program allows MORE fuel to the engine in neutral or park than when in gear and idling. That may or may not be true for all vehicles. Emissions control with three-way catcons is sometimes counterintuitive.

On my wife’s Honda, when you put it in park or neutral, the rpm jumps up slightly and then settles back down after a second indicating that the engine control computer closes the throttle body’s idle bypass slightly in response to the lower load. This would mean a slightly lower fuel consumption with the engine in neutral, ditto for having the AC off.
On cars with a fixed idle throttle opening, the load put on the engine actually lowers the rpm and thus lowers the manifold vacuum which draws less air through the throttle and with it less fuel.

Unless you can confirm that it is not running with a richer mix in neutral, you only have half the story.