Long Term FT Avg

Display shows percentage from -100% to 100%. The center position for the long term fuel trim is 0%. The long term fuel trim is based on short term fuel trim learned values. It is stored in memory blocks of the long term memory according to MAP and RPM values. A percentage greater than 0% indicates that time is being added to the MCV pulse width, increasing the amount of fuel to the engine. A percentage less than 0% indicates time is being subtracted from the MCV pulse width, reducing the amount fuel to the engine. A value of 0% indicates no compensation is required to operate the engine at the desired 16.8 to 1 air/fuel ratio.