engine lexus LS400 1998 Electrical Components / LEXUS 1998 LS400 (OM50498U) Owner's Guide

STARTING AND DRIVING
155
THREEWAY CATALYTIC
CONVERTER
31L0022
Threeway catalytic converters are emission control devices
installed in the exhaust system.
It looks somewhat like a muffler, but its purpose is to reduce
pollutants in the exhaust gas.
CAUTION
Keep people and combustible materials away from the
exhaust pipe while the engine is running. The exhaust gas
is very hot.
Do not drive, idle or park your vehicle over anything that
might burn easily such as grass, leaves, paper or rags.
NOTICE
A large amount of unburned gases flowing into the threeway
catalytic converter may cause it to overheat and create a fire
hazard. To prevent this and other damage, observe the following
precautions:
Use only unleaded gasoline.
Do not drive with an extremely low fuel level; running out of
fuel could cause the engine to misfire, creating an excessive
load on the threeway catalytic converter.
Do not allow the engine to run at idle speed for more than 20
minutes.
Avoid racing the engine.
Do not pushstart or pullstart your vehicle.
Do not turn off the ignition while the vehicle is moving.
Keep your engine in good running order. Malfunctions in the
engine electrical system, electronic ignition
system/distributor ignition system or fuel system could cause
an extremely high threeway catalytic converter
temperature.
If the engine becomes difficult to start or stalls frequently,
take your vehicle in for a checkup as soon as possible.
Remember, your Lexus dealer knows your vehicle and its
threeway catalytic converter system best.

STARTING AND DRIVING
156To ensure that the threeway catalytic converter and the
entire emission control system operate properly, your vehicle
must receive the periodic inspections required by the Lexus
Maintenance Schedule. For scheduled maintenance
information, refer to the separate ”Owner’s Manual
Supplement/ Maintenance Schedule”.
ENGINE EXHAUST CAUTION
CAUTION
Avoid inhaling the engine exhaust. It contains carbon
monoxide, which is a colorless and odorless gas. It can
cause unconsciousness or even death.
Make sure the exhaust system has no holes or loose
connections. The system should be checked from time to
time. If you hit something, or notice a change in the sound
of the exhaust, have the system checked immediately.
Do not run the engine in a garage or enclosed area except
for the time needed to drive the vehicle in or out. The
exhaust gases cannot escape, making this a particularly
dangerous situation.
Do not remain for a long time in a parked vehicle with the
engine running. If it is unavoidable, however, do so only in
an unconfined area and adjust the heating or cooling
system to force outside air into the vehicle.
Keep the trunk lid closed while driving. An open or
unsealed trunk lid may cause exhaust gases to be drawn
into the vehicle. If you must drive with the trunk lid open
to accommodate a large object, close the windows, open all
the dashboard vents and have the heating or cooling system
deliver fresh air into the vehicle by turning the fan to high
speed with the air intake control button in the OUTSIDE
AIR mode.
To allow proper operation of your vehicle’s ventilation
system, keep the inlet grilles in front of the windshield clear
of snow, leaves, or other obstructions.
If you smell exhaust fumes in the vehicle, drive with the
windows open and the trunk lid closed. Have the cause
immediately located and corrected.

STARTING AND DRIVING
157
BEFORE STARTING THE ENGINE
1. Check the area around the vehicle before entering it.
2. Adjust seat position, seatback angle, head restraint height and
steering wheel angle.
3. Adjust inside and outside rear view mirrors.
4. Lock all doors.
5. Fasten seat belts.
Remember to check that the service reminder indicators function
when turning the key to ”ON”, and check the fuel gauge to see that
you have sufficient fuel.
IGNITION SWITCH WITH
STEERING LOCK
31L0011
”START” Starter motor on. The key will return to the ”ON”
position when released.
For starting tips, see page 159.
”ON” Engine on and all accessories on.
This is the normal driving position.
NOTICE
Do not leave the key in the ”ON” position if the engine is not
running. The battery will discharge and the electronic ignition
system/distributor ignition system could be damaged.
”ACC” Accessories such as the radio operate, but the engine
is off.
If you leave the key in the ”ACC” or ”LOCK” position and open the

STARTING AND DRIVING
158driver’s door, a buzzer will remind you to remove the key.*
NOTE: *The volume or interval of beep sound can be changed.
Ask your Lexus dealer for details.
31L0031
”LOCK” Engine is off and the steering wheel is locked. The
ignition key can be removed only at this position.
To turn the key from ”ACC” to the ”LOCK” position, you must put
the transmission selector lever in the ”P” position.
Once you remove the key, the engine immobiliser system is
automatically set. See ”Engine immobiliser system” on page 10.
When starting the engine, the key may seem stuck at the ”LOCK”
position. To free it, first be sure the key is pushed all the way in, and
then rock the steering wheel slightly while turning the key gently.
If, in an emergency, you must turn the engine off while the vehicle
is moving, turn the key only to ”ACC”.
PARKING BRAKE
31L005
1
To set: Fully depress the parking brake pedal.
2
To release: Pull the parking brake release lever.
Before leaving your vehicle, firmly apply the parking brake.
CAUTION
Before driving, make sure the parking brake is fully released
and that the parking brake reminder light is off.

STARTING AND DRIVING
159
HOW TO START THE ENGINE
Before cranking
1. Apply the parking brake firmly.
2. Turn off unnecessary lights and accessories.
3. Put the selector lever in ”P”. If you need to restart the engine
while the vehicle is moving, put the selector lever in ”N”. A starter
safety device will prevent the starter from operating if the selector
lever is in any drive position.
4. Depress the brake pedal and hold it to the floor until you are ready
to drive off.
Starting the engine
Before starting the engine, be sure to follow the instructions in
”Before cranking”.
Normal starting procedure
The multiport fuel injection system/sequential multiport fuel
injection system in your engine automatically controls the proper
airfuel mixture for starting. You can start a cold or hot engine as
follows:
1. With your foot off the accelerator pedal, crank the engine by
turning the key to ”START”. Release it when the engine starts.
2. After the engine runs for about 10 seconds, you are ready to drive.If the weather is below freezing, let the engine warm up for a few
minutes before driving. Do not leave the vehicle while the engine
is warming up.
If the engine stalls ...
Simply restart it , using the correct procedure given in normal
starting.
If the engine will not start
See ”If your vehicle will not start” on page 193.
NOTICE
Do not crank for more than 30 seconds at a time. This may
overheat the starter and wiring systems.
Do not race a cold engine.
If the engine becomes difficult to start or stalls frequently,
have the engine checked immediately.

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160
AUTOMATIC TRANSMISSION
Your automatic transmission has a shift lock system to minimize
the possibility of incorrect operation. This means you can only
shift out of ”P” position when the brake pedal is depressed with
the ignition switch in ”ON” position. ()
31L078
The shift position is displayed on the instrument cluster.P:Parking, engine starting and key removal position
R:Reverse position
N:Neutral position
D:Normal driving position (Shifting into overdrive possible)
4:Position for engine braking (Shifting into overdrive not
possible)
When the cruise control is being used, even if you downshift
from ”D” to ”4”, engine braking will not be applied because
the cruise control is not cancelled. For the operation to
decrease the vehicle speed, see page 170.
3, 2:Position for more powerful engine braking
L:Position for maximum engine braking

STARTING AND DRIVING
161 Correct use of the automatic transmission is explained in the
following parts.
(a) Normal driving
(b) Using engine braking
(c) Using the ”3”, ”2” and ”L” positions
(d) Backing up
(e) Parking
(f) Good driving practice
(g) Rocking your vehicle if stuck
(h) If you cannot shift the selector lever
(i) If the ”ECT PWR” indicator light flashes
(a) Normal driving
31L0072
1
”P” (Park) position 2
”N” (Neutral) position
1. Start the engine as instructed in ”How to start the engine” on
page 159.
The transmission must be in ”P” or ”N”. The engine will not start
in any drive position even if the ignition key is turned to ”START”.

STARTING AND DRIVING
162
31L008-3
1
Power mode 2
Normal mode 3
Snow mode
2. Set the driving pattern selector switch to the ”Normal”
position.
Your transmission has a driving pattern selector switch which allows
you to select ”Power”, ”Normal” or ”Snow” mode to suit your
driving condition. For ordinary driving, Lexus recommends that
you use the ”Normal” position to improve fuel economy.
3. For more powerful acceleration and sporty driving, use the
”Power” position.
In the POWER position, the ”ECT PWR” light in the instrument
cluster is on and the transmission is shifted up at higher vehicle
speeds and shifted down more responsively than in the NORMAL
position.
For ”Snow” mode, see ”Electronic Throttle Control System” on
page 167.
31l0552
1
”D” (Drive) position 2
Brake pedal
4. With your foot holding down the brake pedal, shift the
selector lever to ”D”.
Always use the ”D” position to improve fuel economy and quiet
driving. Only in this position, shifting into the overdrive gear is
possible. However, while the engine coolant temperature is low, the
transmission will not shift into the overdrive gear even in the ”D”
position. (See ”(b) Using engine braking” and ”(f) Good driving
practice” for exceptions.)
CAUTION
Never put your foot on the accelerator pedal while shifting.

STARTING AND DRIVING
163 5. Release the parking brake and brake pedal. Depress the
accelerator pedal slowly for smooth starting.
In normal cruising, the vehicle will start in the first gear and
automatically shift up to the most suitable gear. On inclines, declines
or winding roads, etc., the vehicle shifts up and down automatically
according to the running conditions to obtain the suitable driving
power and engine braking.
In ”4” position, the automatic transmission system will select the
most suitable gear for the running conditions such as hill climbing,
hard towing, etc.
If you need to accelerate rapidly while driving, depress the
accelerator pedal to the full throttle position. This provides more
acceleration by automatically downshifting the transmission to the
next lower gear or beyond, depending on the vehicle speed.
If engine braking is needed, such as in descending a long hill, see ”(b)
Using engine braking”.
(b) Using engine braking
31L010-3
To use the braking power of the engine, downshift the transmission
in the way described below:
1
Shift into the ”4” position. The transmission will downshift to
the fourth gear and engine braking will be obtained.
When the cruise control is being used, even if you downshift
from ”D” to ”4”, engine braking will not be applied because the
cruise control is not cancelled. If you need to decrease the
vehicle speed, see page 170.
2
Shift into the ”3” position. The transmission will downshift to
the third gear when the vehicle speed is or becomes lower than
154 km/h (96 mph) and more powerful engine braking will be
obtained.

STARTING AND DRIVING
164
3
Shift into the ”2” position. The transmission will downshift to
the second gear when the vehicle speed is or becomes lower
than 104 km/h (65 mph) and more powerful engine braking
than that of ”3” position will be obtained.
4
Shift into the ”L” position. The transmission will downshift to
the first gear when the vehicle speed is or becomes lower than
18 km/h (11 mph) and maximum engine braking will be
applied.
CAUTION
Be careful when downshifting on a slippery surface. The
abrupt change in engine speed could cause the vehicle to spin
or skid.
(c) Using the ”3”, ”2” and ”L” positions
The ”3”, ”2” and ”L” positions are used for strong engine braking as
described previously.
With the selector lever in ”3”, ”2” or ”L”, you can start the vehicle
in motion as with the lever in ”D”.
With the selector lever in ”3” or ”2”, the vehicle will start in the first
gear and automatically shift to the third or second gear.
With the selector lever in ”L”, the transmission is engaged in the first
gear.
NOTICE
Be careful not to overrev the engine. Watch the tachometer
to keep engine rpm from going into the red zone. The
approximate maximum allowable speed for each position is
given below for your reference:
”3” 160 km/h (99 mph). . . .
”2” 104 km/h (65 mph). . . .
”L” 68 km/h (42 mph). . . .
Do not continue hill climbing or hard towing for a long time
in the ”3”, ”2” or ”L” position. This may cause severe
automatic transmission damage from overheating. To
prevent such damage, ”4” position should be used in hill
climbing or hard towing.