What is the appropriate range for long-term fuel trim?
1 Answers
Long-term fuel trim values range from negative twenty-three percent to sixteen percent, and it is a numerical parameter. Long-term fuel trim is derived from short-term fuel trim values and represents long-term fuel supply correction. Long-term correction refers to issues such as normal aging of component gaps during usage. Below is relevant information about long-term fuel trim: 1. If the long-term fuel trim value exceeds five percent, it indicates a fault in the engine system. 2. If it is significantly below zero percent (a negative value), it indicates the system is running too rich, and fuel supply should be reduced. 3. If it is significantly above zero percent (a positive value), it indicates the system is running too lean, and the PCM needs to increase fuel supply for compensation.