Page 720 of 2493

8 CHECK VACUUM HOSES AND TUBES
1. Disconnect vacuum hoses between the air control valve (Power steering) and vacuum port, air control valve (Power
steering) and air duct.
2. Check hoses and tubes for cracks, clogging, improper connection or disconnection.
SEF109L
OK or NG
OK©GO TO 9.
NG©Repair hoses or tubes.
9 CHECK IACV-AAC VALVE
Refer to ªComponent Inspectionº, EC-425.
OK or NG
OK©GO TO 11.
NG©GO TO 10.
10 REPLACE IACV-AAC VALVE
1. Replace IACV-AAC valve assembly.
2. Perform ªIdle Air Volume Learningº, EC-55.
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©INSPECTION END
INCMP©Follow the construction of ªIdle Air Volume Learningº.
11 CHECK TARGET IDLE SPEED
1. Turn ignition switch ªOFFº.
2. Reconnect all harness connectors and vacuum hose.
3. Start engine and warm it up to normal operating temperature.
4. Also warm up transmission to normal operating temperature.
+For A/T models with CONSULT-II, drive vehicle until ªFLUID TEMP SEº in ªDATA MONITORº mode of ªA/Tº system indi-
cates less than 0.9V.
+For A/T models without CONSULT-II and M/T models, drive vehicle for 10 minutes.
5. Stop vehicle with engine running.
6. Check target idle speed.
M/T: 700±50 rpm
A/T: 800±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 12.
NG©Perform ªIdle Air Volume Learningº, EC-55.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-424
Page 721 of 2493
12 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-144.
©INSPECTION END
SEF605Y
SEF089X
Component InspectionNJEC1763IACV-AAC VALVENJEC1763S011) Disconnect IACV-AAC valve harness connector.
2) Check IACV-AAC valve resistance.
Condition Resistance
Terminal 2 and terminals 1, 3
20-24W[at 20ÉC (68ÉF)]
Terminal 5 and terminals 4, 6
3) Reconnect IACV-AAC valve harness connector.
4) Remove idle air adjusting unit assembly (IACV-AAC valve is
built-in) from engine.
(The IACV-AAC valve harness connector should remain con-
nected.)
5) Turn ignition switch ªONº and ªOFFº, and ensure the IACV-
AAC valve shaft smoothly moves forward and backward,
according to the ignition switch position.
If NG, replace the IACV-AAC valve.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-425
Page 725 of 2493
4 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect throttle position switch harness connector.
JEF091Y
3. Turn ignition switch ªONº.
4. Check voltage between terminal 5 and engine ground with CONSULT-II or tester.
SEF250W
Voltage: Battery voltage
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M169, F113
+Harness for open or short between throttle position switch and fuse block.
+10A fuse
©Repair harness or connectors.
6 CHECK INPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 40 and throttle position switch harness connector terminal 4.
Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 8.
NG©GO TO 7.
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-429
Page 726 of 2493

7 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between throttle position switch and ECM
+Harness for open or short between throttle position switch and TCM (Transmission Control Module)
©Repair open circuit or short to ground or short to power in harness or connectors.
8 ADJUST THROTTLE POSITION SWITCH IDLE POSITION
Perform Basic Inspection, EC-98.
©GO TO 9.
9 CHECK CLOSED THROTTLE POSITION SWITCH
Refer to ªComponent Inspectionº, EC-431.
OK or NG
OK (With CONSULT-II)©GO TO 10.
OK (Without CONSULT-
II)©GO TO 11.
NG©Replace throttle position switch.
10 CHECK THROTTLE POSITION SENSOR
With CONSULT-II
1. Select ªENGINEº and then select ªDATA MONITORº mode with CONSULT-II.
2. Check voltage of ªTHRTL POS SENº under the following conditins.
Voltage measurement must be made with throttle position sensor installed in vehicle.
MTBL0230
OK or NG
OK©GO TO 12.
NG©Replace throttle position sensor.
11 CHECK THROTTLE POSITION SENSOR
Without CONSULT-II
Check voltage between ECM terminal 92 (Throttle position sensor signal) and ground.
Voltage measurement must be made with throttle position sensor installed in vehicle.
YEC049A
OK or NG
OK©GO TO 12.
NG©Replace throttle position sensor.
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-430
Page 730 of 2493
Diagnostic ProcedureNJEC1774
1 INSPECTION START
Do you have CONSULT-II?
YesorNo
Ye s©GO TO 2.
No©GO TO 3.
2 CHECK OVERALL FUNCTION
With CONSULT-II
1. Start engine and warm it up to normal operation temperature.
2. Select ªINT/V SOL-B1º in ªDATA MONITORº mode with CONSULT-II.
3. Lift-up the vehicle and simulate driving in a suitable gear position.
4. Check the ªINT/V SOL-B1º signal under the following conditions.
SEF758Z
OK or NG
OK©INSPECTION END
NG©GO TO 4.
3 CHECK OVERALL FUNCTION
Without CONSULT-II
1. Start engine and warm it up to normal operation temperature.
2. Lift up the vehicle and simulate driving in a suitable gear position.
3. Check the voltage between ECM terminal 1 and ground under the following conditions.
SEF757Z
OK or NG
OK©INSPECTION END
NG©GO TO 4.
INTAKE VALVE TIMING CONTROL SOLENOID VALVEQG
Diagnostic Procedure
EC-434
Page 731 of 2493

4 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect intake valve timing control solenoid valve harness connector.
SEF149X
3. Turn ignition switch ªONº.
4. Check voltage between terminal 1 and engine ground with CONSULT-II or tester.
SEF619X
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M169, F113
+10A fuse
+Harness for open or short between valve timing control solenoid valve and fuse
©Repair harness or connectors.
6 CHECK OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 1 and intake valve timing control solenoid valve harness connector
terminal 2. Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©Repair open circuit or short to ground to short to power or connectors.
INTAKE VALVE TIMING CONTROL SOLENOID VALVEQG
Diagnostic Procedure (Cont'd)
EC-435
Page 735 of 2493
Diagnostic ProcedureNJEC1778
1 CHECK OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Check the voltage between ECM terminals 10, 19, 54, 55, 56 and ground.
SEF791Z
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK A/T CONTROL INPUT SIGNAL CIRCUIT FOR OPEN
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector and TCM (Transmission Control Module) harness connector.
SEF116Y
3. Check harness continuity between the following terminals.
YEC057A
Refer to Wiring Diagram.
Continuity should exist.
OK or NG
OK©GO TO 3.
NG©Repair harness or connectors.
A/T COMMUNICATION LINEQG
Diagnostic Procedure
EC-439
Page 744 of 2493
Diagnostic ProcedureNJEC0438
1 CHECK OVERALL FUNCTION
With CONSULT-II
1. Start engine.
2. Perform ªPOWER BALANCEº in ªACTIVE TESTº mode with CONSULT-II.
SEF190Y
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-II
1. Start engine.
2. Listen to each injector operating sound.
MEC703B
Clicking noise should be heard.
OK or NG
OK©INSPECTION END
NG©GO TO 2.
INJECTORQG
Diagnostic Procedure
EC-448