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.
Fuel is very flammable liquid. If fuel spills or leaks from the pressurized fuel system, it will cause serious injury or death and facility breakage. Fuel can also irritate skin and eyes. To prevent this, always complete the "FUEL LINE SAFETY PROCEDURE ", while referring to the "BEFORE SERVICE PRECAUTION".
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.

Complete the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION .)
Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
Disconnect the quick release connector as shown in the figure. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION .)

Courtesy of MAZDA MOTORS CORP.
Turn the lever of the SST parallel to the hose as shown in the figure.

Courtesy of MAZDA MOTORS CORP.
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.

Start the fuel pump using the following procedure.

Using M-MDS

Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
Connect the M-MDS to the DLC-2.
Using the simulation function "FP", start the fuel pump. (See ON-BOARD DIAGNOSTIC TEST .)

Without using M-MDS

Remove the fuel pump relay.

Courtesy of MAZDA MOTORS CORP.

CAUTION:

Short the specified terminals because shorting the wrong terminal of the relay and fuse block may cause malfunctions.

Using a jumper wire, short fuel pump relay terminals C and D in the relay and fuse block.

Courtesy of MAZDA MOTORS CORP.

Connect the negative battery cable and operate the fuel pump. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)

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 for restriction or leakage
If it exceeds the specification:
- Fuel line restriction
Fuel pressure

425-505 kPa {4.34-5.14 kgf/cm² , 61.7-73.2 psi}
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 .)
Without using M-MDS
1. Disconnect the negative battery cable to stop the fuel pump. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
Measure the fuel hold pressure after 5 min.
- If not within the specification, inspect the following:
  - Fuel line leakage
Fuel hold pressure

250 kPa {2.55 kgf/cm² , 36.3 psi} or more
Complete the "BEFORE SERVICE PRECAUTION". (See BEFORE SERVICE PRECAUTION .)
Disconnect the SST.
Connect the quick release connector. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION .)
Complete the "AFTER SERVICE PRECAUTION". (See AFTER SERVICE PRECAUTION .)