This is by no means an easy task, but if you feel that you're up to the job, follow these instructions and you should be okay. You get to the Mazda's fuel pump via the rear passenger compartment. Make sure you've got a socket wrench set handy too.
Turn over the car's engine and take off the relay connector that is located beneath the left hand side of the instrument panel. Next purposely stall the engine, then switch off the ignition. Now you need to reconnect the relay connector.
Using the socket wrench detach the negative battery terminal cable. Now remove the cushion from the rear seat by releasing the clips at either end of the seat. You should now see the fuel pump assembly unit. Unfasten the electrical connector, follow this up by removing the access cover for the fuel pump assembly.
Separate the fuel lines that you can now see from the fuel pump assembly and take off the screws positioned on the fuel pump unit. Get rid of the old fuel pump assembly gasket and remove the fuel sending unit's electrical connector. You can now take out the sending unit's mounting nuts before separating the sending unit and the fuel pump.
Fasten the new fuel pump to your sending unit and reattach the mounting nuts. Recouple the fuel sending unit connector and give the fuel tank a new gasket. Mount the fuel pump assembly into the fuel tank securing the pump unit's screws. The fuel lines now need to be reattached to the pump unit.
Almost done. Put the access cover back on, tighten the screws, then rejoin the connector and pump unit. Reconnect both the rear seat cushion and the battery cable and start your engine!
