check engine lexus LS400 1998 Audio System / LEXUS 1998 LS400 (OM50498U) Owner's Guide

IN CASE OF AN EMERGENCY
197 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.
NOTICE
For vehicles equipped with the height control switch, be sure to
turn the ignition switch off before jacking. If this is not done, the
vehicle height adjustment function will operate, which may
cause body damage.
CAUTION
When jacking, be sure to observe the following to reduce the
possibility of personal injury:
Follow jacking instructions.
Do not start or run the engine while your vehicle is
supported by the jack.

IN CASE OF AN EMERGENCY
210
40L026-3
2
Insert your finger, the screwdriver or equivalent into the hole
to push down the shift lock override button. You can shift the
selector lever while pushing the button.
For your safety, keep the brake pedal depressed.
Be sure to have the system checked by your Lexus dealer as soon as
possible.
IF YOU LOSE YOUR KEYS OR
LOCK YOURSELF OUT
Many Lexus dealers can make a new key if you can give them the
key number. Since your vehicle is equipped with the engine
immobiliser system, the dealer will also need your master key.
See the suggestion given in ”Keys” on page 8.
If your keys are locked in the vehicle and you cannot get a duplicate,
many Lexus dealers can still open the door for you, using their
special tools. If you must break a window to get in, we suggest
breaking the smallest side window because it is the least expensive
to replace. Be extremely cautious to avoid cuts from the glass.
Even if you lose only one key, contact your Lexus dealer to make a
new key. If you lose all your master keys, you cannot make new
keys; the whole system must be replaced.

MAINTENANCE
214Your copy of the repair order is proof that all required maintenance
has been performed for warranty coverage. And if any problems
should arise with your vehicle while under warranty, your Lexus
dealer will promptly take care of it. Again, be sure to keep a copy
of the repair order for any service performed on your Lexus.
What about doityourself maintenance?
Many of the maintenance items are easy to do yourself, if you have
a little mechanical ability and a few basic automotive tools. Simple
instructions for how to perform them are presented in Section 6.
If you are a skilled doityourself mechanic, the Lexus service
manuals are recommended. Please be aware that doityourself
maintenance can affect your warranty coverage. See your Owner’s
Guide, Owner’s Manual Supplement or Warranty Booklet for the
details.
GENERAL MAINTENANCE
Listed below are the general maintenance items that should be
performed at the intervals specified. It is recommended that any
problem you notice be brought to the attention of your Lexus dealer
or qualified service shop for their advice.
CAUTION
Make these checks only where adequate ventilation can be
obtained if you run the engine.
Vehicle exterior
Items listed below should be performed from time to time, unless
otherwise specified.
Tire pressure
Check the pressure with a gauge every two weeks, or at least once
a month and adjust as shown on the tire pressure label. See page 241
for additional information.
Tire surface
Check the tires carefully for cuts, damage or excessive wear. See
page 243 for additional information.
Wheel nuts
When checking the tires, make sure to check the nuts for looseness.
Tighten them if necessary.

MAINTENANCE
215 Tire rotation
Rotate the tires every 12000 km (7500 miles). See page 242 for
additional information.
Fluid leaks
Check underneath for leaking fuel, oil, water or other fluid after the
vehicle has been parked for a while. If you smell fuel fumes or notice
any leak, have the cause found and corrected immediately.
Doors and engine hood
Check that all doors, including trunk lid, operate smoothly and all
latches lock securely. Make sure the engine hood secondary latch
secures the hood when the primary latch is released.
Vehicle interior
Items listed below should be checked regularly, e.g. while
performing periodic services, cleaning the vehicle, etc.
Lights
Make sure the headlights, stop lights, tail lights, turn signal lights,
and other lights are working. Check headlight aim.
Service reminder indicators and warning buzzers
Check that all service reminder indicators and warning buzzers
function properly.Steering wheel
Check that it has the specified freeplay. Be alert for changes in
steering condition, such as hard steering, excessive freeplay or
strange noise.
Seats
Check that all front seat controls such as seat adjusters, seatback
recliner, etc. operate smoothly. Check that the head restraints move
up and down smoothly and that the locks hold securely in any latched
position.
Seat belts
Check that the seat belt system such as buckles, retractors and
anchors operate properly and smoothly. Make sure the belt webbing
is not cut, frayed, worn or damaged.
Accelerator pedal
Check the pedal for smooth operation and uneven pedal effort or
catching.
Brake pedal
Check the pedal for smooth operation and the proper clearance and
freeplay. Check the brake booster function.
Brakes
At a safe place, check that the brakes do not pull to one side when
applied.

MAINTENANCE
216Parking brake
Check that the pedal has the proper travel and that, on a safe incline,
your vehicle is held securely with only the parking brake applied.
Automatic transmission ”Park” mechanism
On a safe incline, check that your vehicle is held securely with the
selector lever in ”P” position and all brakes released.
Engine compartment
Items listed below should be checked from time to time, e.g. each
time when refueling.
Washer fluid
Make sure there is sufficient fluid in the tank. See page 261 for
additional information.
Engine coolant level
Make sure the coolant level is between the Upper and Lower lines
on the seethrough reservoir when the engine is cold. See page 233
for additional information.
Battery
Your Lexus has a maintenance free battery. You do not have to add
distilled water. For longer life of the battery, however, see page 253
for additional information.
Brake fluid level
Make sure the brake fluid level is correct. See page 239 for
additional information.Engine oil level
Check the level on the dipstick with the engine turned off and the
vehicle parked on a level spot. See page 230 for additional
information.
Power steering fluid level
Check the level on the dipstick. The level should be in the ”HOT”
or ”COLD” range depending on the fluid temperature. See page 240
for additional information.
Exhaust system
Look for cracks, holes and loose supports. If you notice any change
in the sound of the exhaust or smell exhaust fumes, have the cause
located and corrected immediately. (See engine exhaust cautions in
Section 31.)

MAINTENANCE
217
DOES YOUR VEHICLE NEED
REPAIRING?
Be on the alert for changes in performance and sounds, and visual
tipoffs that indicate service is needed. Some important clues are:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A fluid leak under the vehicle (However, water dripping from the
air conditioning after use is normal.)
Change in exhaust sound (This may indicate a dangerous carbon
monoxide leak. Drive with the windows open and have the
exhaust system checked immediately.)
Flatlooking tires, excessive tire squeal when cornering, uneven
tire wear
Vehicle pulls to one side when driving straight on a level road
Strange noises related to suspension movement
Loss of brake effectiveness, spongy feeling brake pedal, pedal
almost touches floors, vehicle pulls to one side when braking
Engine coolant temperature continually higher than normal
If you notice any of these clues, take your vehicle to your Lexus
dealer as soon as possible. It probably needs adjustment or repair.
CAUTION
Do not continue driving with the vehicle unchecked. It could
result in serious vehicle damage and possibly personal injury.

INTRODUCTION
222Remember that battery and ignition cables carry high
currents or voltages. Be careful of accidentally causing a
short circuit.
Before closing the engine hood, check to see that you have not
forgotten any tools, rags, etc.
Do not drive with the air cleaner removed, or excessive engine
wear could result. Also backfiring could cause a fire in the
engine compartment.
Do not overfill automatic transmission fluid, or the
transmission could be damaged.
Be careful not to scratch the glass surface with the wiper
frame.
PARTS AND TOOLS
Here is a list of parts and tools you will need to perform
doityourself maintenance. Remember all Lexus parts are
designed in metric sizes, so your tools must be metric.
Checking the engine oil level
Parts (if level is low):
Use API grade SH, ”EnergyConserving II” or SJ,
”EnergyConserving” multigrade engine oil or ILSAC
multigrade engine oil. For recommended oil viscosity, see page
232.
Tools:
Rag or paper towel
Funnel (only for adding oil)
Checking the engine coolant level
Parts (if level is low):
Ethyleneglycol coolant
Demineralized or distilled water
Tools:
Funnel (only for adding coolant)

SECTION 6 2
224
SERVICE PROCEDURES AND
SPECIFICATIONS
Engine
Specifications 225. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel 227. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Facts about engine oil consumption 229. . . . . . . . . . . . . . . . . . . . . . . . . . .
Used engine oil 230. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the engine oil level 230. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the engine coolant level 233. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spark plugs 234. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE
226 COOLING SYSTEM
Capacity
Coolant type
10.8 L (11.4 qt., 10.4 lmp.qt.)
Ethylene glycol coolant (Do not use alcohol type.)
FUEL
Fuel type
Octane rating
Only UNLEADED
91 (Research octane number 96) or higher
IGNITION SYSTEM
Spark plug Make DENSO
NGK
Gap
SK20R11
IFR6A11
1.1 mm (0.043 in.)
ELECTRICAL SYSTEM
Battery Maintenance type battery
Specific gravity reading at 20C (68F):
Charging rates Quick charge
Slow charge
Nonmaintenance battery
Open voltage at 20C (68F):
Charging rates
1.260 Fully charged
1.160 Half charged
1.060 Discharged
15A max.
5A max.
12.7V Fully charged
12.3V Half charged
11.9V Discharged
[Voltage that is checked 20 minutes after the key is removed with
all the lights turned off]
5A max.

ENGINE
229
FACTS ABOUT ENGINE OIL
CONSUMPTION
Functions of engine oil
Engine oil has the primary function of lubricating and cooling the
inside of the engine, and plays a major role in maintaining the engine
in proper working order.
Engine oil consumption
It is normal that an engine should consume some engine oil
during normal engine operation. The causes of oil consumption
in a normal engine are as follows.
Oil is used to lubricate pistons, piston rings and cylinders. A thin
film of oil is left on the cylinder wall when a piston moves
downwards in the cylinder. High negative pressure generated
when the vehicle is decelerating sucks some of this oil into the
combustion chamber. This oil as well as some part of the oil film
left on the cylinder wall is burned by the high temperature
combustion gases during the combustion process.
Oil is also used to lubricate the stems of the intake valves. Some
of this oil is sucked into the combustion chamber together with
the intake air and is burned along with the fuel. High temperature
exhaust gases also burn the oil used to lubricate the exhaust valve
stems.The amount of engine oil consumed depends on the viscosity of
the oil, the quality of the oil and the way the vehicle is driven.
More oil is consumed by highspeed driving and frequent
acceleration and deceleration.
A new engine consumes more oil, since its pistons, piston rings and
cylinder walls have not become conditioned.
When judging the amount of oil consumption, keep in mind that
the oil may have become diluted, making it difficult to judge the
true level accurately.
For example, if a vehicle is used for repeated short trips and
consumes a normal amount of oil, the dipstick may not show any
drop in the oil level at all, even after 1000 km (600 miles) or more.
This is because the oil is gradually becoming diluted with fuel or
moisture, making it appear that the oil level has not changed.
The diluting ingredients evaporate out when the vehicle is then
driven at high speeds, as on an expressway, making it appear that oil
is excessively consumed after driving at high speeds.
Importance of engine oil level check
One of the most important points in proper vehicle maintenance is
to keep the engine oil at the optimum level so that oil function will
not be impaired. Therefore, it is essential that the oil level be
checked regularly. Lexus recommends that the oil level be checked
every time you refuel the vehicle.
NOTICE