what does it mean when air is in the fuel tank? on 2004 Ford Explorer Sport Trac

The check engine light came on and had a test done, it said something about there was o2 in the fuel tank

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2 answers
Hello i need to know what was the fault code stored on-board your computer's memory and also were there any drivabilty problems? HAVE A BLESS DAY from DR. RECO.
Hello you will need to find out the fault code stored on-board the vehicle's computer and more info.HAVE A BLESS DAY from DR.RECO.

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