What is Short/Long Fuel Trim?

What is Short/Long Fuel Trim?
Fuel Trim refers to feedback adjustments to the base fuel schedule.

Short Term Fuel Trim refers to dynamic or instantaneous adjustments (i.e., during braking/accelerating).

Long Term Fuel Trim refers to much more gradual adjustments to the fuel calibration schedule than short-term trim adjustments. Long term adjustments compensate for vehicle differences and gradual changes that occur over time.

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