2003 Lexus GX470 check engine

IN CASE OF AN EMERGENCY
382
IF YOU CANNOT SHIFT AUTOMATICTRANSMISSION SELECTOR LEVER
If you cannot shift the selector lever out of “P” position to
other positions even though the brake pedal is d epressed,
use the shift lock override button as follows:
1Turn the ignition key to “LOCK”. Make sure the parking
brake is applied.
2Pry up the cover with a flat−bladed screwdriver or
equivalent.
3Push down the shift lock override button. You can shift out
of “P” position only while pushing the button.
4Shift into “N” position.
Insert the cover. Start the engine. For your safety, keep
the brake pedal depressed.
Be sure to have the system checked by your Lexus dealer as
soon as possible.

MAINTENANCE
396Your 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 do −it− yourself mechanic, the Lexus service
manuals are recommended. Please be aware that
do−it−yourself 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 432 for additional information.
Tire surface
Check the tires carefully for cuts, damage or excessive wear.
See page 434 for additional information.
Wheel nuts
When checking the tires, make sure to check the nuts for
looseness. Tighten them if necessary.

MAINTENANCE
397
Tire rotation
Rotate the
tires according to the maintenance schedule. (For
scheduled maintenance information, please refer to the
“Owner’s Manual Supplement / Scheduled Maintenance”.)
See page 434 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 side doors and back door, 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 free play. Be alert for changes
in steering condition, such as hard steering, excessive free
play 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. For folding −up second and
third seats, and detachable third seat, check that the latches
lock securely.
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 ef fort
or catching.
Brake pedal
Check the pedal for smooth operation and the proper
clearance and free play. Check the brake booster function.
Brakes
At a safe place, check that the brakes do not pull to one side
when applied.

MAINTENANCE
398Parking brake
Check that the lever 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
Check the lock release button of the selector lever for proper
and smooth operation. 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 454 for
additional information.
Engine coolant level
Make sure the coolant level is between the “F” and “L” lines on
the see− through reservoir when the engine is cold. See page
422 for additional information.
Radiator, condenser and hoses
Check that the front of the radiator and condenser are clean
and not blocked with leaves, dirt, or insects. See page 423 for
additional information.
Battery
Check the battery condition by the indicator color. See page
447 for additional information.

MAINTENANCE
399
Brake fluid level
Make sure the brake fluid level is correct. See page 430 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 419 for
additional
information.
Power steering fluid level
Check the level through the reservoir. The level should be in
the “HOT” or “COLD” range depending on the fluid
temperature. See page 431 for additional information.
Exhaust system
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 caution” on page 298.)
DOES YOUR VEHICLE NEED REPAIRING?
Be on the alert for changes in performance and sounds, and
visual tip −offs 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.)
 Flat−looking 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

INTRODUCTION
405
Removing the engine compartment covers
Before checking the power steering fluid or fuses in the
engine compartment, remove the engine compartment
covers as follows:
61PY007
1
Turn the plastic nuts counterclockwise and remove them.
2
Push the core of the clips using a Phillips −head
screwdriver and remove the clips.
3
Remove the covers.
Be careful not to lose the removed plastic nuts and clips.
After checking the items, install the engine compartment
covers and insert the plastic nuts and clips in their original
positions.
When inserting the clips, do as shown above.
NOTICE
After installing the engine compartment covers, make
sure the covers are securely in their original positions.

INTRODUCTION
407
NOTICE
Remember 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 and
power steering fluid, or the transmission and power
steering 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
do−it−yourself 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):
“Toyota Genuine Motor Oil” or equivalent
See page 420 for details about engine oil selection.
Tools:
 Rag or paper towel
 Funnel (only for adding oil)
Checking the engine coolant level
Parts (if level is low):
“Toyota Genuine Long Life Coolant” or equivalent
See “Checking the engine coolant level” on page 422 for
instructions.
 Demineralized or distilled water
Tools:
 Funnel (only for adding coolant)

SECTION 6 – 2
410
SERVICE PROCEDURES AND
SPECIFICATIONS
Engine
Specifications411
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Fuel 414
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Fuel pump shut off system 416
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Facts about engine oil consumption 417
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Used engine oil 418
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Checking the engine oil level 419
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Checking the engine coolant level 422
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Checking the radiator and condenser 423
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Spark plugs 424
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