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Fuel Line Pressure Inspection

Special Service Tool (SST) 

  1. Mazda SST number
  2. Global SST number
  1. 49 N013 1A0D
  2. -

Fuel pressure gauge set
G13698496Courtesy of MAZDA MOTORS CORP.
- -
WARNING:
  • Highly pressurized fuel may spray out if the fuel line is cut. Due to the following dangers occurring with a fuel spray, always complete the "FUEL LINE SAFETY PROCEDURE " to prevent the fuel from spraying.
    • Fuel may cause irritation if it comes in contact with skin and eyes.
    • If fuel ignites and causes a fire, it may lead to serious injury or death, and damage to property and facilities.
  • A person charged with static electricity could cause a fire or explosion, resulting in death or serious injury. Before performing work on the fuel system, discharge static electricity by touching the vehicle body.
CAUTION:
  • Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the quick release connector joint area before disconnecting/connecting using cloth or soft brush, and make sure that it is free of foreign material.
  1. Complete the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION .)
  2. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  3. Disconnect the quick release connector as shown in the figure. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION .)
    G11436320Courtesy of MAZDA MOTORS CORP.
  4. Turn the lever of the SST parallel to the hose as shown in the figure.
    G11436347Courtesy of MAZDA MOTORS CORP.
  5. Insert the SST quick release connector into the fuel pipe until a click is heard.
  6. Verify that the quick release connector is firmly connected by pulling it by hand.
  7. Start the fuel pump using the following procedure.

    Using M-MDS 

    1. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
    2. Connect the M-MDS to the DLC-2.
    3. Using the simulation function "FP", start the fuel pump. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.5T)] .)

      Without using M-MDS 

      1. Remove the fuel pump relay.
        G11436348Courtesy of MAZDA MOTORS CORP.
        CAUTION:
        • Short the specified terminals because shorting the wrong terminal of the relay and fuse block may cause malfunctions.
      2. Using a jumper wire, short fuel pump relay terminals C and D in the relay and fuse block.
        G09074855Courtesy of MAZDA MOTORS CORP.
      3. Connect the negative battery terminal and operate the fuel pump. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  8. Operate the fuel pump for 10 s.
  9. Measure the fuel line pressure.
    • If not within the specification, inspect the following:

      If it less than the specification: 

      • Fuel pump unit
      • Fuel line for restriction or leakage

        If it exceeds the specification: 

      • Fuel line restriction

      Fuel pressure 

      545-695 kPa {5.56-7.08 kgf/cm2 , 79.1-100.0 psi}

  10. Stop the fuel pump using the following procedure.

    Using M-MDS 

    1. Using the simulation function "FP", stop the fuel pump. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.5T)] .)

    Without using M-MDS 

    1. Disconnect the negative battery terminal to stop the fuel pump. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  11. Measure the fuel hold pressure after 5 min.
    • If not within the specification, inspect the following:
      • Fuel line leakage

        Fuel hold pressure 

        175-326 kPa {1.79-3.32 kgf/cm2 , 25.4-47.2 psi}

  12. Complete the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION .)
  13. Disconnect the SST.
  14. Connect the quick release connector. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION .)
  15. Complete the "AFTER SERVICE PRECAUTION". (See AFTER SERVICE PRECAUTION .)