Fuel Pressure: Testing and Inspection
1. INSPECT FUEL PUMP OPERATION
a. Connect the TOYOTA hand-held tester to the DLC3.
b. Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
NOTE: Do not start the engine.
c. Select the active test mode on the TOYOTA hand-held tester.
d. Please refer to the TOYOTA hand-held tester operator's manual for further details.
e. If you have no TOYOTA 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 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 M-fuse, fuses, EFI main relay,fuel pump, ECM and wiring connections.
g. Turn the ignition switch OFF.
h. Disconnect the TOYOTA hand-held tester.
2. CHECK FUEL PRESSURE
a. Check that the battery positive voltage is above 12V.
b. Disconnect the negative (-) terminal cable from the battery.
c. Remove the union bolt and 2 gaskets, and disconnect the fuel inlet pipe from the delivery pipe.
CAUTION:
- Put a suitable container or shop rag under the delivery pipe.
- Slowly loosen the union bolt.
d. Install the fuel inlet pipe and SST (pressure gauge) to the delivery pipe with the 3 gaskets and SST (union bolt).
SST 09268-45012
Torque: 29 Nm (300 kg.cm, 22 ft.lb)
e. Wipe off any splattered gasoline.
f. Connect the TOYOTA hand-held tester to the DLC3.
g. Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
NOTE: Do not start the engine.
h. Select the active test mode on the TOYOTA hand-held tester.
i. Please refer to the TOYOTA hand-held tester operator's manual for further details.
j. If you have no TOYOTA hand-held tester, connect the positive (+) and negative (-) leads from the battery to the fuel pump connector.
k. Reconnect the negative (-) terminal cable to the battery.
l. Turn the ignition switch ON.
m. Measure the fuel pressure.
Fuel pressure:
265-304 kPa (2.7-3.1 kg/Sq.cm, 38-44 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.
n. Remove the TOYOTA hand-held tester.
o. Start the engine.
p. Measure the fuel pressure at idle.
Fuel pressure: 206 - 255 kPa (2.1 - 2.6 kg/Sq.cm, 31 - 37 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 kg/Sq.cm, 21 psi) or more
If pressure is not as specified, check the fuel pump, pressure regulator and/or injector.
s. After checking fuel pressure, disconnect the negative (-) terminal cable from the battery and carefully remove the SST to prevent gasoline from splashing.
SST 09268-45012
t. Reconnect the fuel inlet pipe to the delivery pipe with 2 new gaskets and the union bolt.
Torque: 29 Nm (300 kg.cm, 22 ft.lb)
u. Reconnect the negative (-) terminal cable to the battery.
v. Check for fuel leakage.
3. 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 specified, replace the fuel pump and/or lead wire.
4. INSPECT FUEL PUMP RESISTANCE
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 from burning out.
- Keep the fuel pump as far away from the battery as possible.
- Always do switching at the battery side.
If operation is not as specified, replace the fuel pump and/or lead wire.