Sounds like the fuel pump is toasted. The fuel level sending unit is part of the fuel pump and it can be replaced separately but it would make more sense just to replace the entire fuel pump assembly. Dealer will charge you probably $500.00 or more to replace it, independent shop maybe charges a little less. You can do it yourself, it's not too hard of a job. You can buy a fuel pump for about $225.00 to $250.00 depending on which parts store you use. I bought mine at Advance, regular price was $220.00, I used an online discount code, bought it on their website and picked it up at their store the same day, and it cost me $180.00.