Fuel Pump: Testing and Inspection

1. CHECK FUEL PUMP OPERATION
a. Connect the LEXUS hand-held tester to the DLC3.
b. Turn the ignition switch ON and push the LEXUS hand-held tester main switch ON.

NOTE: Do not start the engine.

c. Select the ACTIVE TEST mode on the LEXUS hand-held tester.
d. Please refer to the LEXUS hand-held tester operator's manual for further details.
e. If you have no LEXUS hand-held tester, connect the positive (+) and negative (-) leads from the battery to the fuel pump connector.




f. Check that there is pressure in the fuel inlet hose from the fuel filter.

HINT: If there is fuel pressure, you will hear the sound of fuel flowing. If there is no pressure, check the fusible link, fuses, EFI main relay, fuel pump, ECM and wiring connections.

g. Turn the ignition switch OFF.
h. Disconnect the LEXUS hand-held tester from the DLC3.




2. CHECK FUEL PRESSURE
a. Check the battery positive voltage is above 12 V.
b. Disconnect the negative (-) terminal cable from the battery.
c. Purchase the new No.1 fuel pipe and take out the fuel tube connector from its pipe.
Part No.23801-20060




d. Remove the fuel hose clamp.




e. Disconnect the No.1 fuel pipe (fuel tube connector) from the fuel filter outlet.

CAUTION:
- Perform disconnecting operations of the fuel tube connector (quick type) after observing the precautions.
- As there is retained pressure in the fuel pipe line, prevent it from splashing inside the engine compartment.




f. Install SST (pressure gauge) as shown in the illustration by using SST and fuel tube connector.
SST 09268-41047, 09268-41250, 09268-45012

g. Wipe off any splattered gasoline.
h. Reconnect the negative (-) terminal cable to the battery..
i. Connect the LEXUS hand held tester to the DLC3. (See step 1. check fuel pump operation a. to e.)

j. Measure the fuel pressure.
Fuel pressure: 301-347 kPa (3.1 -3.5 kg/sq.cm, 44-50 psi)
If pressure is high, replace the fuel pressure regulator.
If pressure is low, check the fuel hoses, fuel hose connections,fuel pump, fuel filter and fuel pressure regulator.

k. Disconnect the LEXUS hand-held tester from the DLC3.
(I) Start the engine.
m. Measure the fuel pressure at idle.
Fuel pressure: 301-347 kPa (3.1-3.5 kg/sq.cm, 44-50 psi)
n. Stop the engine.
o. Check that the fuel pressure remains as specified for 5 minutes after the engine has stopped.
Fuel pressure: 147 kPa (1.5 kg/sq.cm, 21 psi) or more
If pressure is not as specified, check the fuel pump, pressure regulator and/or injectors.
p. After checking fuel pressure, disconnect the negative (-) terminal cable from the battery and carefully remove the SST and fuel tube connector to prevent gasoline from splashing.
SST 09268-41047, 09268-41250, 09268-45012




q. Reconnect the No.1 fuel pipe (fuel tube connector).

CAUTION: Perform connecting operations of the fuel tube connector(quick type) after observing the precautions.




r. Surely install the fuel hose clamp to the fuel filter with "click" sound.
s. After installing the clamp, check that the clamp is fixed by pulling up the clamp.
t. Reconnect the negative (-) terminal cable to the battery.
u. Check for fuel leaks.

3. REMOVE REAR SEAT CUSHION
4. REMOVE FLOOR SERVICE HOLE COVER
5. DISCONNECT FUEL PUMP & SENDER GAUGE CONNECTOR




6. INSPECT FUEL PUMP RESISTANCE
Using an ohmmeter, measure the resistance between terminals 4 and 5.
Resistance: 0.2-3.0 Ohms at 20 °C (68 °F)
If the resistance is not as specified, replace the fuel pump.




7. INSPECT FUEL PUMP OPERATION
Connect the positive (+) lead from the battery to terminal 4 of the connector, and the negative (-) lead to terminal 5. Check that the fuel pump operates.

NOTE:
- These tests must be done quickly (within 10 seconds) to prevent the coil burning out.
- Keep the fuel pump as tar away from the battery as possible.
- Always do the switching at the battery side.
If operation is not as specified, replace the fuel pump or lead wire.

8. RECONNECT FUEL PUMP & SENDER GAUGE CONNECTOR
9. REINSTALL FLOOR SERVICE HOLE COVER
10. REINSTALL REAR SEAT CUSHION