Fuel Tank Inspection: 2WD

Level the vehicle.
Complete the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION .)
Drain the fuel. (See FUEL DRAINING PROCEDURE .)
Using the following procedure:
6:4 split type
- Remove the rear seat cushion. (See REAR SEAT CUSHION REMOVAL/INSTALLATION .)
4:2:4 split type
- Set the rear seat aside as shown in the figure. (See REAR SEAT REMOVAL/INSTALLATION .)
Fig 1: Identifying Rear Seat
Courtesy of MAZDA MOTORS CORP.
Partially peel back the floor mat as shown in the figure.

Fig 2: Identifying Floor Mat
Courtesy of MAZDA MOTORS CORP.
Remove the service hole cover.

Fig 3: Identifying Service Hole Cover And Screws
Courtesy of MAZDA MOTORS CORP.
Disconnect the following parts:
- Fuel pump unit connector
- Quick release connector (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION )
Remove the floor under cover (LH). (See FLOOR UNDER COVER REMOVAL/INSTALLATION .)
Disconnect the HO2S connector.
Remove the TWC and HO2S as a single unit. (See EXHAUST SYSTEM REMOVAL/INSTALLATION )
Remove the fuel tank and fuel pump unit as a single unit. (See FUEL TANK REMOVAL/INSTALLATION )
Perform the following procedure to verify the fuel tank airtightness.
1. Plug the fuel pump unit pipe, ports B and C.
  
  Fig 4: Identifying Fuel Pump Unit Pipe Plugs With Ports B And C
  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 flow leakage from the fuel tank.
  - If there is air flow, replace the fuel tank. (See FUEL TANK REMOVAL/INSTALLATION .)
Plug the fuel pump unit pipe and port B.

Fig 5: Identifying Fuel Pump Unit Pipe Plugs With Ports B
Courtesy of MAZDA MOTORS CORP.
Level the fuel tank.
Apply a pressure of 3 kPa {23 mmHg, 0.9 inHg} to port A and wait for a while.
With the pressure still applied, verify that there is air flow from port C and the pressure is 0-3 kPa {0-23 mmHg, 0-0.9 inHg}.
- If there is no air flow, replace the fuel tank. (See FUEL TANK REMOVAL/INSTALLATION .)
Apply a pressure of -0.5 kPa {-3.8 mmHg, -0.1 inHg} to port A and wait for a while.
With the pressure still applied, verify that there is air flow from port C and the pressure is -0.5-0 kPa {-3.8-0 mmHg, -0.1-0 inHg}.
- If there is no air flow, replace the fuel tank. (See FUEL TANK REMOVAL/INSTALLATION .)
- If there is air flow, place the fuel tank upside down.
Apply a pressure to port A and wait for a while.

Fig 6: Identifying Fuel Pump Unit Pipe Plugs
Courtesy of MAZDA MOTORS CORP.
With the pressure still applied, verify that there is no air flow from port C.
- If there is air flow, replace the fuel tank. (See FUEL TANK REMOVAL/INSTALLATION .)