Fuel Delivery and Air Induction: 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 LEXUS hand-held tester main switch ON.

NOTICE: 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 these parts:
- Fuse
- EFI main relay
- Fuel pump ECU
- 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 that the battery positive voltage is above 12 V.
(b) Disconnect the negative (-) terminals cable from the battery.

(d) Remove the union bolt holding the delivery pipe to the fuel inlet pipe.
- Remove the 2 gaskets.

CAUTION:
- Put a suitable container or shop towel under the delivery pipe.
- Slowly loosen the union bolt.

(e) Install the fuel inlet pipe and SST (pressure gauge) to the delivery pipe with the 3 gaskets and the SST (union bolt).
SST 09268-45012

Torque: 42 N.m (420 kgf.cm, 30 ft.lb)

(f) Wipe off any splattered gasoline.

(g) Connect the LEXUS hand-held tester to the DLC3.

(h) Reconnect the negative (-) terminal cable to the battery.
(i) Turn the ignition switch ON.
(j) Measure the fuel pressure.

Fuel pressure: 265 - 304 kPa
(2.7 - 3.1 kgf/cm2. 38 - 44 psi)

- If pressure is high, replace the fuel pressure regulator.
- If pressure is low, check the following parts:
- Fuel hoses and connections
- Fuel pump
- Fuel filter
- Fuel pressure regulator
(k) Remove the LEXUS hand-held tester from the DLC3.
(l) Start the engine.

(m) Disconnect the vacuum sensing hose from the fuel pressure regulator, and plug the hose end.
(n) Measure the fuel pressure at idle.

Fuel pressure: 265 - 304 kPa
(2.7 - 3.1 kgf/cm2, 38 - 44 psi)

(O) Reconnect the vacuum sensing hose to the fuel pressure regulator.
(P) Measure the fuel pressure at idle.

Fuel pressure:196 - 235 kPa
(2.0 - 2.4 kgf/cm2. 28 - 34 psi)

- If pressure is not as specified, check the vacuum sensing hose and fuel pressure regulator.
(q) Stop the engine.
(r) Check that the fuel pressure remains as specified for 5 minutes after the engine has stopped.

Fuel pressure: 147 kPa
(1.5 kgf/cm2, 21 psi) or more

- If pressure is not as specified, check the fuel pump, pressure regulator and/or injectors.
(s) After checking fuel pressure, disconnect the negative (-) terminal cable from the battery and carefully remove SST to prevent gasoline from splashing. SST 09268-45012
(t) Connect the fuel inlet pipe to the delivery pipe with 2 new gaskets and the union bolt.

Torque: 42 N.m (420 kgf.cm, 30 ft.lb.)

(u) Install the No.2 vacuum pipe with the 2 nuts.

Torque: 27 N.m (280 kgf.cm, 20 ft.lb.)

(v) Reconnect the negative (-) terminal cable to the battery.
(w) Check for fuel leaks.