2005 LEXUS LS430 engine overheat

DRIVING TIPS
383
CAUTION
Before driving off, make sure the parking brake is
fully released and that the parking brake reminder
light is off.
 Do not leave your vehicle unattended while the
engine is running.
 Do not rest your foot on the brake pedal while driving.
It can cause dangerous overheating, needless wear,
and poor fuel economy.
 To drive down a long or steep hill, reduce your speed
and downshift. Remember, if you ride the brakes
excessively, they may overheat and not work
properly. See page 311.
 Be careful when accelerating, upshifting,
downshifting or braking on a slippery surface. The
abrupt change in engine speed, such as sudden
acceleration or engine braking, could cause the
vehicle to skid or spin.
 Do not drive in excess of the speed limit. Even if the
legal speed limit permits it, do not drive over 140 km/h
(85 mph) unless your vehicle has highspeed
capability tires. Driving over 140 km/h (85 mph) may
result in tire failure, loss of control and possible
injury. Be sure to consult a tire dealer to determine
whether the tires on your vehicle are highspeed
capability tires or not before driving at such speeds.
 Do not continue normal driving when the brakes are
wet. If they are wet, your vehicle will require a longer
stopping distance, and it may pull to one side when
the brakes are applied. Also, the parking brake will
not hold the vehicle securely.

DRIVING TIPS
391

Because of the added load of the trailer, your vehicle’s
engine may overheat on hot days (at temperatures over
30 C [85 F]) when going up a long or steep grade with a
trailer. If the engine coolant temperature gauge indicates
overheating, immediately turn off the air conditioning (if in
use), pull your vehicle off the road and stop in a safe spot.
See “If your vehicle overheats” on page 404.
 Always place wheel blocks under both the vehicle and trailer
wheels when parking. Apply the parking brake firmly. Put
the transmission in “P”. Avoid parking on a slope with a
trailer, but if it cannot be avoided, do so only after performing
the following:
1. Apply the brakes and keep them applied.
2. Have someone place wheel blocks under both the vehicle
and trailer wheels.
3. When the wheel blocks are in place, release your brakes
slowly until the blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into “P” and turn off the engine. When restarting out after parking on a slope:
1. With the transmission in “P” position, start the engine. Be
sure to keep the brake pedal depressed.
2. Shift into the “3” (third range), “2” (second range), “\
1” (first
range) or “R” position.
3. Release the
parking brake and brake pedal and slowly pull
or back away from the wheel blocks. Stop and apply your
brakes.
4. Have someone retrieve the blocks.
CAUTION
 Do not exceed 72 km/h (45 mph) or the posted towing
speed limit, whichever is lower. Because instability
(swaying) of a towing vehicletrailer combination
usually increases as the speed increases, exceeding
72 km/h (45 mph) may cause loss of control.
 Slow down and downshift before descending steep
or long downhill grades. Do not make sudden
downshifts.
 Avoid holding the brake pedal down too long or too
frequently. This could cause the brakes to overheat
and result in reduced braking efficiency.

DRIVING TIPS
392
HOW TO SAVE FUEL AND MAKEYOUR VEHICLE LAST LONGER
Improving fuel economy is easy − just take it easy. It will help
make your vehicle last longer, too. Here are some specific tips
on how to save money on both fuel and repairs:
 Keep your tires inflated at the correct pressure. Check
the pressure every two weeks, or at least once a month.
Underinflation causes tire wear and wastes fuel.
 Do not carry unneeded weight in your vehicle. Excess
weight puts a heavier load on the engine, causing greater
fuel consumption.
 Avoid lengthy warmup idling. Once the engine is
running smoothly, begin driving − but gently. Remember,
however, that on cold winter days this may take a little
longer.
 Always keep the automatic transmission selector lever
in the “D” position when engine braking is not required.
Driving with the overdrive off will reduce the fuel economy
(For details, see “Automatic transmission” on page 305.)
 Accelerate slowly and smoothly. Avoid jackrabbit starts.
 Avoid long engine idling. If you have a long wait and you
are not in traffic, it is better to turn off the engine and start
again later.
 Avoid engine overrevving. Use a gear position suitable
for the road on which you are traveling. 
Avoid continuous speeding up and slowing down.
Stop−and−go driving wastes fuel.
 Avoid unnecessary stopping and braking. Maintain a
steady pace. Try to time the traf fic signals so you only need
to stop as little as possible or take advantage of through
streets to avoid traffic lights. Keep a proper distance from
other vehicles to avoid sudden braking. This will also
reduce wear on your brakes.
 Avoid heavy traffic or traffic jams whenever possible.
 Do not rest your foot on the brake pedal. This causes
premature wear, overheating and poor fuel economy.
 Maintain a moderate speed on highways. The faster you
drive, the greater the fuel consumption. By reducing your
speed, you will cut down on fuel consumption.
 Keep the front wheels in proper alignment. Avoid hitting
the curb and slow down on rough roads. Improper
alignment not only causes faster tire wear but also puts an
extra load on the engine, which, in turn, wastes fuel.
 Keep the bottom of your vehicle free from mud, etc.
This not only lessens weight but also helps prevent
corrosion.

SECTION 4
399
IN CASE OF AN EMERGENCY
In case of an emergency
If your engine stalls while driving400
. . . . . . . . . . . . . . . . . . . . . . . . . . .
If your vehicle will not start 400
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If you cannot increase engine speed 404
. . . . . . . . . . . . . . . . . . . . . . . .
If your vehicle overheats 404
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If you have a flat tire 405
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
.
If your vehicle becomes stuck 415
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If your vehicle needs to be towed 416
. . . . . . . . . . . . . . . . . . . . . . . . . .
If you cannot shift automatic transmission
selector lever 423
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . .
If you lose your keys or lock yourself out 424
. . . . . . . . . . . . . . . . . . . .

IN CASE OF AN EMERGENCY
401
NOTICE
Do not pull or pushstart the vehicle. It may damage
the vehicle or cause a collision when the engine starts.
Also the threeway catalytic converter may overheat
and become a fire hazard.
If the engine turns over at its normal speed but will not
start
1. If the engine will not start, the engine may be flooded
because of repeated cranking. See “(b) Starting a flooded
engine” for further instructions.
2. If the engine still will not start, it needs adjustment or repair.
Call a Lexus dealer, Roadside Assistance or Customer
Service Assistance. (See “Foreword”.)
(b) Starting a flooded engine
If the engine will not start, your engine may be flooded
because of repeated cranking.
If this happens, turn the ignition switch to “START” with the
accelerator pedal fully depressed. Continue this operation for
30 seconds and then stop cranking. Then try starting the
engine with your foot off the accelerator pedal.
If the engine does not start after 30 seconds of cranking,
release the ignition switch, wait a few minutes and try again.
If the engine still will not start, it needs adjustment or repair.
Call a Lexus dealer, Roadside Assistance or Customer
Service Assistance. (See “Foreword”.)
NOTICE
Do not crank for more than 30 seconds at a time. This
may overheat the starter and wiring systems.
(c) Jump starting
To avoid serious personal injury and damage to your
vehicle which might result from battery explosion, acid
burns, electrical burns, or damaged electronic
components, these instructions must be followed
precisely.
If you are unsure about how to follow this procedure, we
strongly recommend that you seek help from your Lexus
dealer, Roadside Assistance or Customer Service Assistance.
(See “Foreword”.)

IN CASE OF AN EMERGENCY
404
IF YOU CANNOT INCREASEENGINE SPEED
If engine speed does not increase when the accelerator
pedal is depressed, there may be a problem somewhere
in the electronic throttle control system . Move the vehicle
to a safe place by means of creeping and call a Lexus
dealer for assistance:
1. Depress the brake pedal and shift to the “D” position.
2. Gradually release the brake pedal, and the vehicle starts to
move by creeping. After arriving at a safe place, stop the
vehicle and call a Lexus dealer for assistance.
CAUTION
 The above method of moving the vehicle is for
emergency. Use it only for moving minimum
distances to a safe place.
 Be especially careful to prevent erroneous pedal
operation.
IF YOUR VEHICLE OVERHEATS
If your engine coolant temperature gauge indicates
overheating, if you experience a loss of power, or if you
hear a loud knocking or pinging noise, the engine has
probably overheated.
When the engine overheats
Pull safely off the road, stop the vehicle and turn on your
emergency flashers. Put the transmission in “P” and apply the
parking brake.
A: If steam is coming from your engine:
Turn off the engine. Leave the hood closed until there is no sign
of steam or coolant. Your engine could have been seriously
damaged already. Call your Lexus dealer for assistance.
CAUTION
To help avoid personal injury, keep the hood closed until
there is no steam. Escaping steam or coolant is sign of
very high pressure.

IN CASE OF AN EMERGENCY
405
B: If no steam is coming from your engine:
Leave the engine running and turn off the air conditioning.
Check the following.

Is the cooling fan operating?
 Is the coolant in the acceptable range?
 Is the engine drive belt O.K.?
CAUTION
When the engine is running, keep hands and clothing
away from the moving fan and engine drive belt.
 Do not attempt to remove the radiator cap when the
engine and radiator are hot. Serious injury could
result from scalding hot fluid and steam blown out
under pressure.
If the cooling fan is not operating or the coolant is not in the
acceptable range, turn off the engine and call your Lexus
dealer.
If both conditions are O.K., after the engine coolant
temperature has cooled to normal, continue driving your
vehicle.
If the engine coolant temperature does not cool down, or your
vehicle overheats again, have it checked as soon as possible
by your Lexus dealer.
IF YOU HAVE A FLAT TIRE
1. Reduce your speed gradually, keeping a straight line.
Move cautiously off the road to a safe place − well away
from the traffic. Avoid stopping on the center divider of
a highway. Park on a level spot with firm ground.
2. Stop the engine and turn on your emergency flashers.
3. Firmly set the parking brake and put the transmission
in “P”.
4. Have everyone get out of the vehicle on the side away
from traffic.
5. Read the following instructions thoroughly.
CAUTION
When jacking, be sure to observe the following to
reduce the possibility of personal injury:
 Follow jacking instructions.
 Do not put any part of your body under a vehicle
supported by a jack. Otherwise, personal injury
may occur.
 Do not start or run the engine while your vehicle
is supported by the jack.