Fuel Pressure and Hold Inspections

WARNING: Before performing the following operation, release the fuel pressure from the fuel system to reduce the possibility of injury or fire.

SST Fuel Gauge With Pressure Release Hose:

Fuel Pressure/Fuel Pressure Hold Inspections

1. Install the SST.
2. key ON, engine oft.
3. Connect the SST (NGS) to the data link connector and select Active Command Mode.
4. Select Output Test Mode. Press MODE to change to the "ALL ON" mode, and press start to run fuel pump.
5. Turn relay OFF.
6. Observe the fuel pressure.


Fuel pressure: 240-280 kPa (35-40 psi)

- Zero or pressure low - Check the fuel pump.
- Pressure high - Perform pressure regulator high pressure inspection.
- If as specified, the fuel line or fuel filter might be clogged or restricted.

7. Observe the fuel pressure after 1 min.

Fuel pressure: Within 34 kPa (2-5 psi) of reading in test step 5.

8. If not as specified, perform the following inspections:
- Pressure regulator diaphragm inspection.
- Injector fuel leakage test.
- If results of fuel line pressure and pressure hold inspection are OK, perform "Fuel Pressure Under Load Inspection".