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Home >> Chevrolet >> 1999 >> Metro L4-079 1.3L VIN 2 MFI >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Scan Tool Testing and Procedures >> Scan Tool Data Definitions - Powertrain Systems >> Total Fuel Trim
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Total Fuel Trim

The scan tool displays a positive or negative percentage. The value of the Total Fuel Trim is obtained by putting values of Short Term FT and Long Term FT together. The Total Fuel Trim value indicates how much correction is necessary to keep the air/fuel mixture at stoichiometrical 14:7:1 ratio.
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