Lexus ES300 (1997 year). Service manual — part 518

S05456

LEXUS

Hand–Held Tester

S05353

S05359

Fuel Tube Connector

SF05N–05

S06086

Fuel Hose
Clamp

SF–6

–

SFI

FUEL PUMP

857

1997 LEXUS ES300 (RM511U)

FUEL PUMP

ON–VEHICLE INSPECTION

1.

CHECK FUEL PUMP OPERATION

(a)

Connect the LEXUS hand–held tester to the DLC3.

(b)

Turn the ignition switch ON and LEXUS hand–held tester
main switch ON.

NOTICE:
Do not start the engine.
(c)

Select the active test mode on the LEXUS hand–held tes-
ter.

(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 pos-
itive (+) and negative (–) leads from the battery to the fuel
pump connector. (See step 7)

(f)

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

HINT:
If there is fuel pressure, you will hear the sound of fuel flowing.
If there is no pressure, check these parts:

Fusible link

Fuses (AM2 30A, IGN 5A)

EFI main relay

Fuel pump

ECM

Wiring connections

(g)

Turn the ignition switch to LOCK.

(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 bat-
tery.

(c)

Purchase the new No.1 fuel pipe and take out the fuel
tube connector from its pipe.
Part No. 23801–20040

(d)

Remove the fuel hose clamp.

S05352

S05364

SST

(Hose)

SST

SST
(Hose)

Retainer

No.1 Fuel
Pipe

SST

Fuel Tube
Connector

SST

(Hose)

–

SFI

FUEL PUMP

SF–7

858

1997 LEXUS ES300 (RM511U)

(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 precau-
tions.

As there is retained pressure in the fuel pipe line, pre-
vent it from splashing inside the engine compart-
ment.

(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.)

(j)

Measure the fuel pressure.
Fuel pressure:
301 – 347 kPa (3.1 – 3.5 kgf/cm

2

, 44 – 50 psi)

If pressure is high, replace the fuel pressure regulator.
If pressure is low, check these parts:

Fuel hoses and connections

Fuel pump

Fuel filter

Fuel pressure regulator

(k)

Disconnect the LEXUS hand–held tester from the DLC3.

(l)

Start the engine.

(m)

Measure the fuel pressure at idle.
Fuel pressure:
301 – 347 kPa (3.1 – 3.5 kgf/cm

2

, 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 kgf/cm

2

, 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

09268–41046, 09268–41250, 09268–45012

S05351

S06086

Fuel Hose
Clamp

S04508

Ohmmeter

4

5

S04509

Battery

4

5

SF–8

–

SFI

FUEL PUMP

859

1997 LEXUS ES300 (RM511U)

(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 leakage.

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

Ω

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.
NOTICE:

These tests must be done quickly (within 10 seconds)
to prevent the coil burning out.

Keep the fuel pump as far 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

SF05O–04

S04745

Rear Seat Cushion

Floor Service Hole Cover

Fuel Pump & Sender
Gauge Connector

No.1 Fuel Tank Protector

Fuel Tank Vent Tube Set Plate

Fuel Hose

Fuel Pump Connector

Fuel Pump

Fuel Pump Filter

Clip

Rubber Cushion

Gasket

Fuel Pump Assembly

N·m (kgf·cm, ft·lbf)

Non–reusable part

: Specified torque

x8

4 (40, 35 in.·lbf)

–

SFI

FUEL PUMP

SF–9

860

1997 LEXUS ES300 (RM511U)

COMPONENTS