Can ECO Mode Be Kept On for a Long Time?

[MacMaddox]

ECO mode can be kept on for a long time in a car. ECO mode, also known as economy mode, is particularly effective in saving fuel when driving in congested urban traffic conditions. When ECO mode is active, the carbon buildup in the engine is roughly the same as in normal driving mode, so ECO mode can be left on continuously. The main principle of ECO mode is not complicated. It involves the ECU control unit comprehensively analyzing and judging factors such as automatic transmission gear shifts, engine speed, vehicle speed, braking, and transmission oil temperature—all of which affect fuel consumption—to calculate the optimal fuel supply for the engine. This effectively reduces fuel consumption compared to normal driving modes. In simple terms, it controls the engine speed with appropriate gear shifts to minimize unnecessary fuel consumption. ECO is an abbreviation, with its Chinese translation representing Ecology (environmental protection), Conservation (energy saving), and Optimization (power). ECO mode is further divided into active ECO driving mode and passive ECO driving mode. When the ECO indicator on the dashboard lights up, it means the vehicle's economy mode is activated. ECO mode can be either active or passive. The difference lies in the fact that active ECO mode has a dedicated button, allowing the driver to choose whether to enable it. When the driver presses the ECO mode switch, the dashboard indicator lights up, and the vehicle automatically adjusts settings such as throttle opening, transmission shift logic, and air conditioning output. Passive ECO mode does not have a dedicated button; when the dashboard ECO indicator lights up, it serves as a reminder. The system automatically evaluates the driver's behavior, and if the current driving operation achieves optimal fuel supply, the ECO indicator will appear on the dashboard. Most cars use active ECO driving mode, meaning they have a dedicated switch button. Therefore, in daily driving, ECO mode can generally be kept on. However, it is unnecessary to activate ECO mode when driving at speeds over 120 km/h, idling, in N/P gear, or in manual mode—especially when climbing hills. In these situations, ECO mode may not demonstrate its fuel-saving benefits and could even affect performance. Additionally, ECO mode usually becomes ineffective under the following conditions: When the vehicle speed exceeds 120 km/h, the system prioritizes speed, and ECO mode automatically deactivates. When idling or in N/P gear or manual mode, ECO mode may also become ineffective. When high torque output is required, such as when climbing a hill, the engine control unit prioritizes delivering sufficient power to drive the vehicle, and ECO mode will not function.

[DiMadison]

Actually, driving in ECO mode for daily commuting is super convenient. I've basically never turned it off in the three years I've had this car. The biggest difference is the throttle response becomes gentler, making starts and acceleration smoother without sudden jerks, which saves a lot of fuel during daily traffic jams on the elevated roads. The dashboard shows the long-term fuel consumption dropped from 9.2 to 8.1. The A/C cooling might be slightly slower, but it's not a big deal. Just remember to manually turn it off during prolonged uphill drives, otherwise the transmission tends to stay in high gears and may lug. It's perfectly fine for city driving—in fact, it even protects the engine. The mechanic said during maintenance that carbon buildup is less than in normal mode. However, if you're hitting the highway or in a hurry, you’ll definitely need to turn it off for more power.