Some 2021 F-150 PowerBoost vehicles may exhibit the fuel door release tappet separated from the fuel door housing, slow fuel fill, fuel spit back during refueling, a message in the cluster that states Close Fuel Door To Avoid Check Engine Light and/or diagnostic trouble code (DTC) P04B5 stored in the powertrain control module (PCM). This may be due to opening the fuel door without pressing the fuel door release button. Prior to following normal diagnostics, first check that the fuel door release tappet is properly installed into the fuel door and that the fuel door closes properly and opens when using the fuel door release button. If the tappet has separated from the fuel door press the fuel door release button to eject the tappet from the latch then reinstall the tappet into the fuel door by pressing it into place with features aligned with the fuel door.
