Fuel Pressure Inspection (Low-Pressure System)

Release the residual pressure in the fuel line. (Refer to Fuel System - Repair Procedures - "Releasing Residual Pressure in Fuel Line")

Install the Special Service Tool (SST).

1. Disconnect the low pressure fuel feed tube from the high pressure fuel pump inlet.
2. Install the special service tool to measure the fuel pressure between the low-pressure fuel feed hose and the low-pressure inlet of the high-pressure fuel pump (see the illustration below).

   

Inspect for fuel leaks at the connections between the low-pressure fuel feed hose, the low-pressure inlet of the high-pressure fuel pump, and the SST with the ignition ON.

Measure the fuel pressure.

1. Start the engine and measure fuel pressure at idle.

   Fuel pressure: 500 kPa (5.1 kgf/cm², 72.5 psi)

   Fuel Pressure	Cause	Related Part
   Too low	Clogged fuel filter	Fuel filter
   	Fuel leakage	Fuel Pressure Regulator
   Too high	Fuel pressure regulator stuck	Fuel Pressure Regulator

2. Stop the engine, and then check the change in the fuel pressure gauge reading. Specification: the gauge reading should remain near the value after 5 minutes of engine stop.

   Fuel Pressure (After Engine Stop)	Cause	Related Part
   Fuel pressure drops slowly	Injector leakage	Injector
   Fuel pressure drops immediately	Fuel pump check valve stuck open	Fuel pump

3. Turn the ignition off.

Release the residual pressure in the fuel line. (Refer to Fuel System - Repair Procedures - "Releasing Residual Pressure in Fuel Line")

End of test

1. Remove the special service tool (SST) from the low-pressure fuel feed tube and the low-pressure inlet of the high-pressure fuel pump.
2. Connect the low-pressure fuel feed tube and the hose to the low-pressure inlet of the high-pressure fuel pump.