2002 Chevy Trailblazer,2WD,92K miles. My gas mileage is ridiculously poor

I see no answers here and this hasn't been helpful at all... I'm getting hardly 10 mpg... Can anyone explain what's going on? I had a friend that had a similar size SUV of another maker (Pacifica) experiencing the same horrible gas mileage everyone was thinking transmission, tune-up whatever; however, they vehicle showed a code for the catalytic converter during the complete computer diagnostic test … Sure enough order the item had it installed ..WHAM-O… problem solved.. Does anyone know what solves this problem for the 2003 Trail Blazer 4.2ltr? Please help a single mother three kids and need the help seriously.

Fuel level sensor issues are not uncommon for the 2002 Chevrolet Trailblazer. That however should not affect your actual fuel mileage. The calculated fuel mileage may be incorrect if you are using the fuel gauge to determine the fuel used. The most accurate way to calculated fuel mileage is to use the trip meter to register the miles driven between fill-ups and the gallons filled at each fill-up. On board system are only as accurate as the fuel sensor readings, which in your case are incorrect.

any check engine lights on, may just need a tune up