Short Term FT Bank 1

Range (-100 to 100 Percent)
A change made to the fuel delivery will be indicated by the Long and Short Term Fuel Trim values. The Short Term Fuel Trim values change rapidly in response to the HO2S signal voltages. These changes fine tune the engine fueling. The Long Term Fuel Trim values change in response to the trends in the Short Term Fuel Trim. The Long Term Fuel Trim makes coarse adjustments to the fueling in order to re-center and restore control to the Short Term Fuel Trim. The Short Term Fuel Trim and the Long Term Fuel Trim can be monitored with a scan tool. A positive Fuel Trim value indicates that the ECM is adding fuel in order to compensate for a lean condition. A negative Fuel Trim value indicates that the ECM is reducing the amount of fuel in order to compensate for a rich condition.