Fuel Pump: Testing and Inspection

INSPECTION








Using Scan tool

Check Item: Fuel Pump.
Drive: Fuel Pump is driven to circulate fuel.
Check Conditions: Engine cranking, Forced drive of Fuel Pump.
- Hold return hose with fingers to feel pulsation indicating fuel flow
- Verify pulsation is felt.
- Listen to pump operating sound near Fuel Tank
- Verify operating sound is heard.

Harness Inspection Procedure





1. Check the Fuel Pump.
- Apply battery voltage to the checking terminal and operate the pump.
- Fuel Pump should run.

If OK - go to step 4.
If not OK - go to step 2.





2. Check the ground circuit of the Fuel Pump.
- Connector disconnected.

If OK - go to step 3.
If not OK - Repair the harness (I 2-Ground).





3. Check for continuity between the Fuel Pump and the checking terminal.
- Connector disconnected

If OK - go to step 4.
If not OK - Repair the harness (I1 - J1).





4. Measure the power supply voltage of the MFI Control Relay.
- MFI Control Relay connector disconnected.
- Ignition Switch START (when H6 checked).
- Voltage should read 8 volts or more.

If OK - go to step 5.
If not OK - Repair the harness (H 1 - Battery) (H 6 - Ignition switch).





5. Check for an open circuit, or a short circuit to ground between the MFI Control Relay and the Engine Control Module.
- MFI Control Relay connector disconnected.
- Engine Control Module connector disconnected.

If OK - go to step 6.
If not OK - Repair the harness (H 8 - C50-4 6).





6. heck for continuity of the ground circuit.
- MFI Control Relay connector disconnected.

If OK - go to step 7.
If not OK - Repair the harness (H 7 - Ground).





7. Check for an open circuit, or a short circuit to ground between the MFI Control Relay and the Fuel Pump.
- MFI Control Relay connector disconnected.
- Fuel Pump connector disconnected.

If OK - END.
If not OK - Repair the harness (H4 - I1).