Does Coasting in Neutral Save or Waste Fuel?

[DakotaDella]

Not necessarily fuel-saving, and may even waste fuel. Many modern vehicles are equipped with electronically controlled fuel injection systems. When the car is shifted into neutral, the ECU defaults to assuming the car is idling, thereby increasing fuel injection to maintain idle speed. The electronic fuel injection control system inherently has fuel reduction or cutoff functions. Shifting to neutral in such scenarios not only disables these functions but also increases fuel injection. Fuel-saving tips: 1. Smooth Driving: One of the most practical and effective fuel-saving methods is maintaining steady driving. For small-displacement vehicles, it's best to keep speeds between 60 to 80 km/h, while for larger-displacement vehicles, maintain speeds between 80 to 100 km/h. 2. Avoid Congested Routes: Before driving, check the route. If it's congested, it's best to detour. In traffic jams, the car not only can't move but also remains in an operating state, which wastes fuel. 3. Reduce Vehicle Weight: The weight of the car also increases fuel consumption. Therefore, if some items in the car are temporarily not needed, try to remove them to reduce the vehicle's weight.

[VonAngela]

Recently, while driving my manual transmission car, I wondered if shifting to neutral would save more fuel, only to discover it's a common misconception. When a manual car coasts in neutral, the engine does idle, consuming fuel to maintain idle speed—approximately 0.1-0.2 liters per minute. In contrast, coasting in gear (e.g., downhill) reduces engine speed to a certain level, prompting the electronic control system to cut off fuel injection, resulting in near-zero fuel consumption. From a safety perspective, coasting in neutral poses greater risks: without engine braking, stopping distances increase by over 25%, especially on slippery roads or steep slopes, raising the chance of skidding or losing control. Daily driving habits like staying in gear also reduce transmission wear. I recommend avoiding neutral coasting for short-term convenience—opting for gear-based operation is both more efficient and safer.

[Brandon]

As a seasoned driver with decades of experience, I can confirm that coasting in neutral did save a bit of fuel in older manual transmission vehicles due to the less precise carburetor systems. However, my new automatic transmission car is completely different: when coasting in gear, the ECU cuts off fuel supply automatically, consuming almost no fuel; whereas shifting to neutral forces the engine to idle, actually burning 0.5-1 liter more per 100 kilometers. From a safety perspective, I once narrowly avoided a crash on a steep slope when I was younger by quickly regaining control of the steering wheel after coasting in neutral. With today's advanced technology, it's best to abandon old habits—coasting in gear is not only more fuel-efficient and stable but also simpler for maintenance. In practical driving, adopting this good habit can reduce monthly fuel consumption by about 10%, saving you dozens of dollars on gas each month in the long run.

[PresleyDella]

As an enthusiast of automotive technology, I've researched the fuel consumption issue when coasting in neutral. Modern vehicle ECU systems optimize fuel efficiency, enabling fuel cut-off during gear coasting which reduces fuel consumption by 30-40%. When shifting to neutral, the engine must maintain idle speed, wasting fuel energy unnecessarily. This is particularly noticeable in hybrid vehicles where regenerative braking can recover energy. From an environmental perspective, reducing idle fuel consumption prevents several kilograms of carbon emissions annually. In terms of driving habits, choosing gear coasting enhances overall safety - why not adopt this practice? A simple adjustment can lead to greener mobility.