Fuel Pump: Testing and Inspection

Fig. 24 Fuel Pump Bypass Terminal I.D.:

Avoid sparks or open flame when checking fuel pump delivery rate.
1. Remove fuel pump relay and install a jumper wire with an in-line switch across sockets to energize the fuel pump, Fig. 24.
2. Disconnect oxygen sensor heating element.
Note: Do not open fuel tank cap until after fuel delivery rate has been checked.
3. Disconnect line from fuel pump at input to fuel filter and collect fuel in suitable calibrated container.
4. Run fuel pump for 30 seconds.
5. Fuel delivery rate should be:
1000 ml @ 12 volts
850 ml @ 11 volts
700 ml @ 10 volts
550 ml @ 9 volts
6. If delivery rate is not within specification, check for kinked or clogged fuel line, or a plugged pickup screen in the fuel tank. If no faults are found in the fuel path, check the voltage supply and current draw of the pump.
7. Disconnect electrical connectors at fuel pump under the car.
8. Connect a voltmeter across leads and turn jumper wire switch ON. Battery voltage should be available. Do not let positive connection contact ground.
9. Turn jumper wire switch off, then connect ground lead to fuel pump.
10. Connect ammeter between positive lead and fuel pump, then turn jumper wire switch ON and check amperage. Amperage draw should not be more than 8.5 amps. Do not let positive connection contact ground.
11. If amperage exceeds 8.5 amps, replace fuel pump.
12. Turn off jumper wire switch, remove ammeter and attach wires to fuel pump.
13. If no other faults are found, replace fuel pump and retest.