Is a Long-Term Fuel Trim of -14.7 Rich or Lean?

[SanMaria]

Long-Term Fuel Trim -14.7 indicates a rich condition. Below is relevant information: 1. Fuel Standard: Generally, the long-term fuel trim parameter ranges from -23% to 16%. A value of 0 means the fuel supply does not require compensation to achieve the correct mixture concentration. A positive value indicates that the injection system needs to inject additional fuel, meaning the engine's air-fuel mixture is lean, and the vehicle may have difficulty starting. A negative value means the fuel injection system needs to reduce fuel delivery to correct an overly rich mixture. Therefore, when the long-term fuel trim is negative, it indicates the vehicle's mixture is too rich. 2. Long-Term Fuel Trim Standard: Typically ±5%. If it exceeds this range, it is highly likely that the engine has a fault. If the vehicle's fuel injectors are clogged, both the fuel injection volume and atomization effect will be poor, resulting in a lean combustible mixture in the engine cylinders.