Page 1513 of 2543

(d) Disconnect the water bypass hose (from the water outlet)
from the throttle body.
(e) Remove the throttle body and gasket.
INSTALLATION HINT: Use a new gasket.
INSPECTION OF THROTTLE BODY
Throttle Body
1. CLEAN THROTTLE BODY
(a) Using a soft brush and carburetor cleaner, clean the cast
parts.
(b) Using compressed air, clean all the passages and apertures.
NOTICE: To prevent deterioration, do not clean the throttle
position sensor, dashpot and throttle opener.
2. INSPECT THROTTLE VALVE
(a) Disconnect the throttle opener vacuum hose from the throttle
body.
(b) Apply vacuum to the throttle opener.
(c) Check that there is no clearance between the throttle stop
screw and throttle lever when the throttle valve is fully closed.
(d) Reconnect the throttle opener vacuum hose to the throttle
body.
Throttle Position Sensor
1. INSPECT THROTTLE POSITION SENSOR
(See on±vehicle inspection)
2. IF NECESSARY, ADJUST THROTTLE POSITION
SENSOR
(a) Loosen the 2 set screws of the sensor.
± ENGINESFI SYSTEM (2JZ±GE)EG±223
Page 1514 of 2543
(b) Insert a 0.50 mm (0.020 in.) feeler gauge between the throttle
stop screw and stop lever.
(c) Connect the tester probe of an ohmmeter to the terminals IDL
and E2 of the sensor.
(d) Gradually turn the sensor clockwise until the ohmmeter
deflects, and secure it with the 2 set screws.
(e) Recheck the continuity between terminals IDL and E2.
Clearance between
lever and stop screw
Continuity (IDL±E2)
0.40 mm (0.016 in.) Continuity
0.60 mm (0.024 in.) No continuity
EG±224± ENGINESFI SYSTEM (2JZ±GE)
Page 1515 of 2543
IDLE AIR CONTROL (IAC) VALVE
ON±VEHICLE INSPECTION
1. INSPECT IAC VALVE FOR OPERATING SOUND
Check that there is a clicking sound immediately after stop-
ping the engine.
If operation is not as specified, check the IAC valve, wiring
and ECM.
2. California only:
INSPECT AIR ASSIST SYSTEM
A. Warm up engine
Allow the engine to warm up to normal operating tempera-
ture.
B. Check idle speed
Idle speed (Transmission in neutral position):
700 + 50 rpm
C. Check IAC valve operation
With engine idling, pinch the air hose and check that engine
speed drops, and then returns back up to idle speed.
If operation is not as specified, check the IAC valve, wiring
and ECM.
3. INSPECT IAC VALVE RESISTANCE
Using an ohmmeter, measure the resistance between the ter-
minals (B1 (or B2) to others).
Resistance:
At 20°C (68°F) 18±22
If the resistance is not as specified, replace the IAC valve.
± ENGINESFI SYSTEM (2JZ±GE)EG±225
Page 1516 of 2543
COMPONENTS FOR REMOVAL AND
INSTALLATION
EG±226± ENGINESFI SYSTEM (2JZ±GE)
Page 1517 of 2543
IAC VALVE REMOVAL
1. REMOVE THROTTLE BODY
(See throttle body removal)
2. REMOVE IAC VALVE FROM THROTTLE BODY
Remove the 2 screws, IAC valve and O±ring.
IAC VALVE INSPECTION
INSPECT IAC VALVE OPERATION
(a) Apply battery voltage to terminals B1 and B2, and while
repeatedly grounding S1±S2±S3±S4±S 1 in sequence, and
check that the valve moves toward the closed position.
(b) Apply battery voltage to terminals B1 and B2, and while
repeatedly grounding S4±S3±S2±S1±S 4 in sequence,
check that the valve moves toward the open position.
If operation is not as specified, replace the IAC valve.
IAC VALVE INSTALLATION
1. INSTALL IAC VALVE TO THROTTLE BODY
(a) Install a new O±ring on the throttle body.
(b) Install the IAC valve with the 2 screws.
2. INSTALL THROTTLE BODY
(See throttle body installation)
± ENGINESFI SYSTEM (2JZ±GE)EG±227
Page 1518 of 2543
ACOUSTIC CONTROL INDUCTION
SYSTEM (ACIS)
ON±VEHICLE INSPECTION
1. CONNECT VACUUM GAUGE
Using a 3±way connector, connect vacuum gauge to the vac-
uum hose between the actuator and VSV.
2. START ENGINE
3. INSPECT ACIS
(a) While the engine is idling, check that the vacuum gauge
needle does not move.
(b) Rapidly depress the accelerator pedal to fully open position
and check that the vacuum gauge needle momentarily
fluctuates approx. 33.3 kPa (250 mmHg, 9.84 in.Hg) or more.
(The actuator rod is pulled down.) If operation is not as
specified, check each part.
4. REMOVE VACUUM GAUGE
Remove the vacuum gauge, and reconnect the vacuum hose
to their proper locations. EG±228
± ENGINESFI SYSTEM (2JZ±GE)
Page 1519 of 2543
Vacuum Tank
COMPONENTS FOR REMOVAL AND
INSTALLATION
VACUUM TANK REMOVAL
Installation is in the reverse order of removal.
1. REMOVE OIL DIPSTICK AND GUIDE FOR A/T
(a) Remove the bolt.
(b) Pull out the dipstick guide together with the dipstick.
INSTALLATION HINT: Apply soapy water to the O±ring, and
push in the dipstick guide.
(c) Remove the O±ring from the dipstick guide.
INSTALLATION HINT: Use a new O±ring.
2. REMOVE VACUUM TANK AND VSV ASSEMBLY
(a) Remove the 2 nuts, and disconnect the vacuum tank from the
intake manifold.
Torque: 21 NVm (210 kgfVcm, 15 ftVlbf)
± ENGINESFI SYSTEM (2JZ±GE)EG±229
Page 1520 of 2543
(b) Disconnect the connector and hoses, and remove the
vacuum tank and VSV assembly:
(1) VSV connector
(2) Vacuum hose (from air intake chamber) from port B of
vacuum tank
(3) Vacuum hose (from actuator) from VSV
3. REMOVE VSV FROM VACUUM TANK
(a) Disconnect the vacuum hose from port A of the vacuum tank.
(b) Remove the screw and VSV.
VACUUM TANK INSPECTION
INSPECT VACUUM TANK
(a) Check that air flows from port A to B.
(b) Check that air does not flow from port B to A.
(c) Plug port B with your finger, and apply 53.3 kPa (400 mmHg,
15.75 in.Hg) of vacuum to port A, and check that there is no
change in vacuum after 1 minute.
If operation is not as specified, replace the vacuum tank.
VSV INSPECTION
(See VSV for ACIS) EG±230
± ENGINESFI SYSTEM (2JZ±GE)