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.