Code P046, Front-To-Rear Bank Fueling Difference: Action

PCM turns on MIL.

1. If any other codes are present, diagnose them first because they can cause a fueling imbalance.
2. Checks for a physical or mechanical problem causing Code P046 to set.
3. Injector bank that is farthest from neutral value of 128 is bank which is out of fuel control. Refer to PCM DATA CODES under DIAGNOSTIC PARAMETERS. See Figure .

Fig 1: Code P046 Schematic, Front-To-Rear Bank Fueling Difference

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code P046 Diagnostic Flow Chart, Front-To-Rear Bank Fueling Difference

Courtesy of GENERAL MOTORS CORP.