fuel pump, fuel filter, and relay ..
 

im planning to change my fuel pump, and filter but want to check where the parts are located... is the pump in the trunk on a 98 a4 2.8?.... any help?.. and what the voltage reading should be on the relay.. thanks in advance

Pump is in the tank, accessed through a panel in the trunk floor. It's a 12v system and you should see that 12v at the switched output of the relay - I haven't seen a varying voltage on these, but current would vary depending on load. You can also check the voltage at the pump harness on top of the tank access cover.