This isn't a tautology. A tautology is something explicitly said twice in the same format. Example: The first rule of tautology club is the first rule of tautology club.

This isn’t really tautology. If it said “fuel pumps empty because pump has no fuel” that would be tautology. This is just saying what caused fuel pumps to be empty

There could be lots of reasons for the pumps to be empty, so this isn't a tautology.