Fuel Line Pressure Inspection

WARNING:

Fuel line spills and leakage from the pressurized fuel system are dangerous. Fuel can ignite and cause serious injury or death and damage. To prevent this, complete the following inspection with the engine stopped.

Follow " BEFORE SERVICE PRECAUTION " before performing any work operations to prevent fuel from spilling from the fuel system.
Remove the battery cover. (See BATTERY REMOVAL/INSTALLATION [L3] ).
Disconnect the negative battery cable.
Disconnect the quick release connector (in the engine compartment). (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION ).
Turn the lever of the SST parallel to the hose as shown in the figure.
Insert the SST quick release connector into the fuel pipe until a click is heard.
Verify that the quick release connector is firmly connected by pulling it by hand.
Connect the negative battery cable.

Fig 1: Inspecting Fuel Line Pressure
Courtesy of MAZDA MOTORS CORP.
Ground the following PCM terminal 1AR using a jumper wire.
Turn the ignition switch to the ON position to start the fuel pump.
Operate the fuel pump for 10 s.
Measure the fuel line pressure.
- If not within the specification, inspect the following:
  If it less than the specification:
  - Fuel pump unit
  - Fuel line leakage
  If it exceeds the specification:
  - Pressure regulator
Fuel line pressure (Reference)

350-410 kPa {3,57-4.18 kgf/cm ² , 50.8- 59.4 psi}

Fig 2: PCM Connector Terminal Identification
Courtesy of MAZDA MOTORS CORP.
Turn the ignition switch to the LOCK position to stop the fuel pump.
Measure the fuel hold pressure after 5 min.
- If not within the specification, inspect the following:
  - Fuel line for clogging or leakage
    Fuel hold pressure (Reference)
    
    250 kPa {2.55 kgf/cm ² , 36.3 psi} or more
Disconnect the SST.
Connect the quick release connector. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION ).
Inspect all related parts by performing " AFTER SERVICE PRECAUTION ".