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Fuel Trim Code Troubleshooting Tips

1. Using the HDS scan tool, access and write down the Freeze Frame Data (which is the data stored at the time the diagnostic code was set). This information can give valuable clues about the operating conditions at the time the code occurred and may reduce the amount of diagnosis and testing required to repair the vehicle.

A. Connect the scan tool and identify the vehicle.

B. Select 1, ENGINE" under the "Select System " menu.

C. Select CODES & DATA MENU from the engine "Main Menu".

D. Select FREEZE FRAME to retrieve the engine operating conditions that were present at the moment the DTC was set.

2. Check the vehicle to identify if codes other than Fuel Trim codes or driveability symptoms are present. A malfunction of any of the following components may affect the Fuel Trim values:

^ Oxygen Sensors ^ Air Flow Sensor
^ Evaporative Emission System ^ Coolant Temperature Sensor
^ Intake Air Temperature Sensor ^ Fuel Injector
^ Throttle Position Sensor

If codes other than Fuel Trim codes are present, diagnose/repair these conditions before continuing with Fuel Trim diagnosis.