Fuel Pump: Testing and Inspection

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

1. Ensure that there is free flow through fuel filter and associated lines.
2. Ensure that the battery is fully charged.
3. Remove fuel pump relay from position 10 on fuse/relay panel, then install a jumper wire with an in-line switch (US 4480/3 or equivalent) in its place, Fig. 24. Ensure that remote control switch is OFF.
4. Remove fuel filler cap, then detach fuel return line at connection and place open end into a suitable measuring container. Use an extension hose if necessary and ensure that measuring container has a capacity of at least one liter.
5. Activate remote control for 30 seconds and measure amount of fuel delivered.
With the engine OFF, pump ON, the amount of fuel delivered should be:
760 ml @ 12 volts
600 ml @ 11 volts
460 ml @ 10 volts
330 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, or a plugged fuel filter. 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.