Idle LEXUS GS400 2000 Service User Guide

EM0D0±01
A00982
CO/HC Meter
± ENGINE MECHANICAL (2JZ±GE)CO/HC
EM±1
1355 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CO/HC
INSPECTION
HINT:
This check is used only to determine whether or not the idle
CO/HC complies with regulations.
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system connected
(d) All accessories switched OFF
(e) All vacuum lines properly connected
(f) SFI system wiring connectors fully plugged
(g) Ignition timing checked correctly
(h) Transmission in neutral position
(i) Tachometer and CO/HC meter calibrated by hand
2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180
SECONDS
4. INSERT CO/HC METER TESTING PROBE AT LEAST
40 cm (1.3 ft) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT
IDLE AND/OR 2,500 RPM
HINT:
When doing the 2 mode (2,500 rpm and idle) test, follow the
measurement order prescribed by the applicable local regula-
tions.

EM±2
± ENGINE MECHANICAL (2JZ±GE)CO/HC
1356 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
If the CO/HC concentration does not comply with regulations,
troubleshoot in the order given below.
(a) Check heated oxygen sensors operation.
(See page DI±44)
(b) See the table below for possible causes, and then inspect
and correct the applicable causes if necessary.
HCCOPhenomenonCauses
HighNormalRough idle1. Faulty ignitions:

Incorrect timing

Fouled, shorted or improperly gapped plugs

Open or crossed high±tension cords
2. Incorrect valve clearance
3. Leaky intake and exhaust valves
4. Leaky cylinder
HighLowRough idle
(Fluctuating HC reading)1. Vacuum leaks:

PCV hose

Intake manifold

Throttle body

Cylinder head gasket
2. Lean mixture causing misfire
HighHighRough idle
(Black smoke from exhaust)1. Restricted air filter
2. Plugged PCV valve
3. Faulty SFI systems:

Faulty pressure regulator

Faulty ECM

Faulty injector

Faulty throttle position sensor

Faulty mass air flow meter

B01982
LEXUS
Hand±Held
Tester
EM0D3±02
A02667
TC
E1 SST
DLC1
A02668
Igniter
White Lead Wire
A02637
EM±12
± ENGINE MECHANICAL (2JZ±GE)IGNITION TIMING
1366 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
IGNITION TIMING
INSPECTION
1. WARM UP ENGINE
Allow the engine to warm up to normal operating temperature.
2. CONNECT LEXUS HAND±HELD TESTER OR OBDII
SCAN TOOL
(a) Connect the LEXUS hand±held tester or OBDII scan tool
to the DLC3.
(b) Please refer to the LEXUS hand±held tester or OBDII
scan tool operator's manual for further details.
3. CONNECT TIMING LIGHT TO ENGINE
4. CHECK IDLE SPEED (See page EM±13)
5. INSPECT IGNITION TIMING
(a) Using SST, connect terminals TC and E1 of the DLC1.
SST 09843±18020
(b) Connect the timing light clip to the white lead wire.
NOTICE:
Use a timing light that can detect the primary signal.
(c) Using a timing light, check the ignition timing.
Ignition timing: 10 ± 2° BTDC @ idle
(Transmission in neutral position)
(d) Remove the SST from the DLC1.
6. FURTHER CHECK IGNITION TIMING
Ignition timing: 6 ± 16° BTDC @ idle
(Transmission in neutral position)
HINT:
The timing mark moves in a range between 6° and 16°.
7. DISCONNECT TIMING LIGHT FROM ENGINE
8. DISCONNECT LEXUS HAND±HELD TESTER OR
OBDII SCAN TOOL

EM0D4±01
± ENGINE MECHANICAL (2JZ±GE)IDLE SPEED
EM±13
1367 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
IDLE SPEED
INSPECTION
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system connected
(d) All accessories switched OFF
(e) All vacuum lines properly connected
(f) SFI system wiring connectors fully plugged
(g) Ignition timing checked correctly
(h) Transmission in neutral position
2. CONNECT LEXUS HAND±HELD TESTER OR OBDII SCAN TOOL (See page EM±12)
3. INSPECT IDLE SPEED
(a) Race the engine speed at 2,500 rpm for approx. 90 seconds.
(b) Check the idle speed.
Idle speed: 700 ± 50 rpm
If the idle speed is not as specified, check the throttle body.
4. DISCONNECT LEXUS HAND±HELD TESTER OR OBDII SCAN TOOL

A11128
Accelerator Pedal Position Sensor Connector
Throttle Control Motor Connector
Throttle Body and Intake Air Connector Assembly
Water Bypass HoseVSV Connector
for EVAP
EVAP Hose
 Gasket Air Assist Hose Engine Wire
Oil Filler Cap
No.3 Timing Belt Cover
Gasket
No.2 Timing Belt Cover
GasketThrottle
Position
Sensor
Connector
Vacuum Hose
(from Actuator for ACIS)
Water Bypass Hose
Engine Wire Protector
High±Tension
Cord w/ Clamp
No.1 Cylinder
Head Cover
Gasket
Timing Belt
x 6
Timing Belt Guide
Gasket
x 5 No.1 Timing Belt Cover
Crankshaft
Pulley
21 (210, 15)
Drive Belt Tensioner
330 (3,300, 243)
Camshaft
Timing Pulley
(VVT±i Pulley)81 (810, 60)
Straight
Screw Plug
15 (150, 11)Seal Washer
Camshaft
Timing Oil
Control Valve
Camshaft Timing
Oil Control
Valve Connector Gasket
Oil Control Valve Filter
 O±Ring
No.1 Oil PipeUnion Bolt
55 (550, 41)
Idler Pulley
Crankshaft Timing Pulley
Timing Belt Plate
Timing Belt Tensioner
N´m (kgf´cm, ft´lbf) : Specified torque
35 (350, 26)

8.0 (80, 71 in.´lbf)
27 (270, 20)
 Non±reusable part

Precoated part
Dust Boot
Engine Wire ClampPCV Hose
Vacuum Hose
(from No.2
Vacuum Pipe)
± ENGINE MECHANICAL (2JZ±GE)TIMING BELT
EM±15
1369 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

A02642
A02719
10 mm
Hexagon
Wrench
A02746
SST
Bolt
EM±20
± ENGINE MECHANICAL (2JZ±GE)TIMING BELT
1374 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
22. REMOVE TIMING BELT
HINT:
(When re±using timing belt):
Draw an arrow on the timing belt in the direction of engine revo-
lution, and place matchmarks on the timing belt and crankshaft
timing pulley.
23. REMOVE IDLER PULLEY
Using a 10 mm hexagon wrench, remove the pivot bolt, plate
washer and idler pulley.
24. REMOVE CRANKSHAFT TIMING PULLEY
(a) Remove the bolt and timing belt plate.
(b) Remove the crankshaft timing pulley.
If the pulley cannot be removed by hand, use SST and bolt (di-
ameter: 8 mm, pitch: 1.5 mm) to remove the crankshaft timing
pulley.
SST 09950±50012 (09951±05010, 09952±05010,
09953±05020, 09954±05010)
Bolt: Part No. 90119±18001
NOTICE:

Do not scratch the sensor part the crankshaft timing
pulley.

Do not turn the timing pulley.

EM0D7±03
EM0126
No!
P02283
Turn
P02075
± ENGINE MECHANICAL (2JZ±GE)TIMING BELT
EM±21
1375 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT TIMING BELT
NOTICE:

Do not bend, twist or turn the timing belt inside out.
Do not allow the timing belt to come into contact with
oil, water or steam.

Do not utilize timing belt tension when installing or re-
moving the mount bolt of the camshaft timing pulley.
If there are any defects, as shown in the illustrations, check the
following points.
(a) Premature parting

Check for proper installation.

Check the timing cover gasket for damage and
proper installation.
(b) If the belt teeth are cracked or damaged, check to see if
either camshaft is locked.
(c) If there is noticeable wear or cracks on the belt face,
check to see if there are nicks on the side of the idler
pulley lock.
(d) If there is wear or damage on only one side of the belt,
check the belt guide and the alignment of each pulley.
(e) If there is noticeable wear on the belt teeth, check timing
cover for damage and check gasket has been installed
correctly and for foreign material on the pulley teeth.
If necessary, replace the timing belt.
2. INSPECT IDLER PULLEY
(a) Visually check the seal portion of the idler pulley for oil
leakage.
If leakage is found, replace the idler pulley.
(b) Check the turning smoothness of the idler pulley.
If necessary, replace the idler pulley.
3. INSPECT DRIVE BELT TENSIONER
Check the turning smoothness of the tensioner.
If necessary, replace the tensioner.
4. INSPECT TIMING BELT TENSIONER
(a) Visually check tensioner for oil leakage.
HINT:
If there is only the faintest trace of oil on the seal on the push
rod side, the tensioner is all right.
If leakage is found, replace tensioner.

EM0D8±04
A02644
Inward
A02720
A0264110 mm Hexagon Wrench
Adhesive
A02658
Timing
Mark
Dot Mark
A02642
± ENGINE MECHANICAL (2JZ±GE)TIMING BELT
EM±23
1377 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
1. INSTALL CRANKSHAFT TIMING PULLEY
(a) Align the pulley set key with the key groove of the pulley.
(b) Slide on the timing pulley facing the flange side inward.
NOTICE:
Do not scratch the sensor part of the crankshaft timing
pulley.
(c) Install the timing belt plate with the bolt.
Torque: 8.0 N´m (80 kgf´cm, 71 in.´lbf)
2. INSTALL IDLER PULLEY
(a) Apply adhesive to 2 or 3 threads of the pivot bolt.
Adhesive:
Part No. 08833±00080, THREE BOND 1344,
LOCTITE 242 or equivalent
(b) Using a 10 mm hexagon wrench, install the plate washer
and pulley with the pivot bolt.
Torque: 35 N´m (350 kgf´cm, 26 ft´lbf)
(c) Check that the pulley bracket moves smoothly.
3. TEMPORARILY INSTALL TIMING BELT
NOTICE:
The engine should be cold.
(a) Use the crankshaft pulley bolt to turn the crankshaft, and
align the dot mark on the crankshaft timing pulley and the
timing mark on the oil pump body.
(b) Remove any oil or water on the crankshaft timing pulley
and idler pulley, and keep them clean.
(c) Install the timing belt on the crankshaft timing pulley and
idler pulley.
HINT:
When re±using timing belt:
Align the matchmarks of the crankshaft timing pulley and timing
belt, and install the belt with the arrow pointing in the direction
of engine revolution.

± INTRODUCTIONFOR ALL OF VEHICLES
IN±17
17 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
CAUTION:
If large amount of unburned gasoline flows into the converter, it may overheat and create a fire haz-
ard. To prevent this, observe the following precautions and explain them to your customer.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid running the engine at idle speed for more than 20 minutes.
(c) Avoid spark jump test.
(1) Perform spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
(2) While testing, never race the engine.
(d) Avoid prolonged engine compression measurement.
Engine compression tests must be done as rapidly as possible.
(e) Do not run engine when fuel tank is nearly empty.
This may cause the engine to misfire and create an extra load on the converter.
(f) Avoid coasting with ignition turned off.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
3. IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM
For vehicles with mobile communication systems such as two±way radios and cellular telephones, observe
the following precautions.
(1) Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic
system.
(2) Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the ve-
hicle's electronic systems. For details about ECU and sensors locations, refer to the section on
the applicable component.
(3) Avoid winding the antenna feeder together with other wiring as much as possible, and also avoid
running the antenna feeder parallel with other wire harnesses.
(4) Check that the antenna and feeder are correctly adjusted.
(5) Do not install powerful mobile communications system.
4. FOR USING OBD II SCAN TOOL OR LEXUS HAND±HELD TESTER
CAUTION:
Observe the following items for safety reasons:

Before using the OBD II scan tool or LEXUS hand±held tester, the OBD II scan tool's instruction
book or LEXUS hand±held tester's operator manual should be read thoroughly.

Be sure to route all cables securely when driving with the OBD II scan tool or LEXUS hand±held
tester connected to the vehicle. (i.e. Keep cables away from feet, pedals, steering wheel and
shift lever.)

Two persons are required when test driving with the OBD II scan tool or LEXUS hand±held tes-
ter, one person to drive the vehicle and the other person to operate the OBD II scan tool or LEX-
US hand±held tester.

Important Points in the Customer Problem Analysis

What ±±±±± Vehicle model, system name

When ±±±±± Date, time, occurrence frequency

Where ±±±±± Road conditions

Under what conditions? ±±±±± Running conditions, driving conditions, weather conditions

How did it happen? ±±±±± Problem symptoms
(Sample) Engine control system check sheet.
ENGINE CONTROL SYSTEM Check Sheet
Customer's Name
Driver's Name
Data Vehicle
Brought in
License No.
Model and Model
Year
Frame No.
Engine Model
Odometer Reading
km
miles
Problem Symptoms
Engine does
not Start
Difficult to
Start
Poor Idling
Poor
Drive ability
Engine Stall
Others
Engine does not crankNo initial combustionNo complete combustion
Engine cranks slowly
Other
Incorrect first idleIdling rpm is abnormalHigh ( rpm)Low ( rpm)
Rough idling
Other
HesitationBack fireMuffler explosion (after±fire)Surging
Knocking
Other
Soon after startingAfter accelerator pedal depressed
After accelerator pedal released
During A/C operation
Shifting from N to D
Other
Data Problem
ConstantSometimes ( times per day/month)
Inspector's
Name
CUSTOMER PROBLEM ANALYSIS CHECK
IN±22± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
22 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
1. CUSTOMER PROBLEM ANALYSIS
In troubleshooting, the problem symptoms must be confirmed accurately and all preconceptions must be
cleared away in order to give an accurate judgment. To ascertain just what the problem symptoms are, it is
extremely important to ask the customer about the problem and the conditions at the time it occurred.
Important Point in the Problem Analysis:
The following 5 items are important points in the problem analysis. Past problems which are thought to be
unrelated and the repair history, etc. may also help in some cases, so as much information as possible should
be gathered and its relationship with the problem symptoms should be correctly ascertained for reference
in troubleshooting. A customer problem analysis table is provided in Diagnostics section for each system
for your use.