Mazda MX-5 Miata Sport 2007 Manual page 1361

2. Remove the battery cover.
3. Disconnect the negative battery cable. (See BATTERY REMOVAL/INSTALLATION [LF] .)
4. Remove the fuel tank with the fuel pump unit. (See FUEL TANK REMOVAL/INSTALLATION
[LF] .)
5. Perform the following procedure to verify the fuel tank airtightness.
1. Plug the fuel pump unit pipe, port B and port C.
Fig. 18: Identifying Plug Fuel Pump Unit Pipe & Ports
Courtesy of MAZDA MOTORS CORP.
2. Apply a pressure of 3 kPa {23 mmHg, 0.9 inHg} to port A and wait for a while.
3. Verify that there is no air leakage from the fuel tank.
If there is airflow, replace the fuel tank.

6. Plug the fuel pump unit pipe and port B.
2007 Mazda MX-5 Miata Sport
2007 ENGINE Fuel System - MX-5 Miata