What does ECO mean in automatic transmission?

[PeytonLee]

ECO in automatic transmission refers to the car's economical driving mode. ECO is an English abbreviation derived from the words Ecology (environmental protection), Conservation (energy saving), and Optimization (power). The Eco mode is further divided into active Eco driving mode and passive Eco driving mode. When the ECO indicator light on the dashboard illuminates, it indicates that the vehicle's economical mode has been activated. The Eco mode can be either active or passive. The difference lies in the fact that the active mode has a dedicated button, allowing the driver to choose whether to activate it. When the driver presses the Eco mode switch, the dashboard indicator light will immediately turn on, and the vehicle will automatically adjust settings such as throttle opening, transmission shift logic, and air conditioning output power. The passive Eco mode does not have a dedicated button. When the ECO indicator light on the dashboard illuminates, it serves only as a reminder function. The Eco mode will automatically assess your driving behavior. If your current driving operation achieves the optimal fuel supply, the dashboard will simultaneously display the ECO indicator light. Most cars use the active Eco driving mode, meaning they have a dedicated switch button. In daily driving, we can generally activate the Eco mode. However, there is no need to enable it when driving at speeds exceeding 120 km/h, during idle parking, in N/P gear, or in manual mode, especially when climbing hills. In such cases, activating the Eco mode would not reflect its economical fuel-saving characteristics and could even impact the vehicle's power performance. Additionally, the Eco mode typically becomes ineffective under the following conditions: When the vehicle speed exceeds 120 kilometers per hour, the car prioritizes speed, and the Eco mode automatically deactivates. During idle parking or in N/P gear and manual mode, the Eco mode may also become ineffective. When high torque output is required, such as when climbing a hill, the engine control unit will prioritize ensuring sufficient power to drive the vehicle, and the Eco mode will not function.

[DominicFitz]

I've driven automatic transmissions for ten years, and Eco mode is a real fuel-saving helper. Press that button, and the car seems to change its personality—the throttle becomes gentler, acceleration slows down a notch, the transmission shifts up early, and the engine runs lazily. Once on the highway with Eco mode on, I found the car roaring but not moving when trying to overtake, so I had to turn it off. It's quite suitable for city traffic jams, saving a lot on fuel. However, the air conditioning also weakens, which isn't great on hot days. If you want more responsive power, it's best to switch back to normal mode before hitting the highway.

[VonPiper]

Last time I took my family on a self-driving trip, I specifically tried the Eco mode and found it completely changed the power response. The car's reaction became noticeably slower, with gentle throttle input resulting only in smooth acceleration without any sudden surges. The engine maintained low RPMs, with the tachometer rarely exceeding 2000 RPM, and gear shifts were particularly eager. This tuning is ideal for family cars with children, ensuring a more comfortable ride for passengers. However, it felt inadequate on mountain roads, where even flooring the pedal resulted in sluggish acceleration. In summer, the air conditioning took longer to cool, so I recommend switching modes according to road conditions.

[LaTyler]

When car owners ask about the principle of Eco mode during car repairs, simply put, it's a fuel-saving program. It achieves this by limiting power output: reducing throttle sensitivity, delaying throttle response, shifting gears earlier, and also restricting air conditioning power. It can save about 15% on fuel costs during low-speed urban driving. However, when the vehicle load or gradient exceeds 3%, this mode will noticeably underperform. If you use Eco mode for a long time, remember to occasionally drive at high speeds to avoid excessive carbon buildup in the throttle.

[MacMiguel]

I drove my new car in Eco mode every day since I got it, and after three months, the fuel consumption has indeed decreased. The transmission's working logic has noticeably changed, with slower starts and more aggressive upshifts, and the engine sound seems muffled. The most obvious change is the throttle lag, which often leads to being cut off by other drivers. However, lane changes in congested areas feel safer, as the throttle isn't too sensitive to cause scratches. The air conditioning cooling becomes weaker, so it's better to turn it on in advance. The most challenging situation is starting on a slope with passengers; it's recommended to turn off Eco mode before going up a bridge. Overall, it's suitable for urban commuting.