Fuel Pressure: Testing and Inspection
SYSTEM INTEGRITY CHECK- Visually inspect the complete fuel delivery system, including fuel tank lines, reservoir, filter, pumps, injectors, pressure regulator, battery, electrical lines and connectors for leakage, looseness, cracks, pinching, kinking, corrosion, grounding, abrasion, or other damage caused by accident, collision, assembly or usage.
- Verify the the battery is fully charged.
- Check the engine fuse integrity.
- Check for sufficient fuel in the fuel tanks.
- If the system is free of any evidence of leakage, damage, or any other cause for concern, continue with the pressure test.
Diagnostic Lead:
STATIC PRESSURE TEST
- Perform Fuel Pressure Relief procedure.
- Install the fuel pressure gauge.
- With the key "OFF", ground the fuel pump lead of the Self-Test connector.
- Key "ON", engine "OFF" to operate the fuel pump.
- Verify that the observed fuel pressure is within specification. Specifications
PRESSURE LEAKDOWN CHECK
- Run fuel pump for 10 seconds and note pressure (ground FP lead of self test connector and turn ignition switch to the "RUN" position).
- Turn off pump and monitor pressure for 60 seconds (disconnect ground or turn ignition switch to "OFF" position).
- Fuel line pressure should remain within 34 kPa (5 psi) of shut off pressure for 60 seconds.
FUEL PRESSURE UNDER LOAD
- Remove and block vacuum line to pressure regulator.
- Run vehicle at idle and then increase engine speed to 2000 rpm or more in short bursts. Fuel pressure should remain within specifications.
NOTE: Operating vehicle under load (road test) should give same results.
NOTE: Additional testing of the fuel system is located at Fuel Delivery and Air Induction/Testing and Inspection. Testing and Inspection