Operation CHARM: Car repair manuals for everyone.
Home >> Pontiac >> 1999 >> Sunfire L4-144 2.4L DOHC VIN T SFI >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Scan Tool Testing and Procedures >> Scan Tool Data, Normal Values and Definitions >> Scan Tool Data Definitions - Powertrain Systems >> Engine Scan Tool Data Definitions >> Long Term FT

Long Term FT

Range - 0-255 (-100% to 100%)
The Long Term Fuel Trim (FT) is derived from the short term fuel trim value. The Long Term Fuel Trim (FT) is used for the long term correction of the fuel delivery. A value of the 128 counts (0%) indicates that the fuel delivery requires no compensation in order to maintain a 14.7:1 air to fuel ratio. A value below 128 counts means that the fuel system is too rich and the fuel delivery is being reduced. The PCM is decreasing the injector pulse width. A value above 128 counts indicates that a lean condition exists for which the PCM is compensating.
pro multis · About Operation CHARM