FICM uses 2 separate circuits (banks) to fire the injectors.
If the wiring for any of the 4 injectors is compromised, all those cylinders will shut down and set code 2146--- or 2149.
Bank 1 => 1,4,6,7
Bank 2 => 2,3,5,8
It is NOT the injector-! GM has a repair connector-- also some part stores.
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