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If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure...
1. Pull safely off the road, stop the ve-
hicle and turn on your emergency
flashers. Put the transmission in “P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the
radiator or reservoir, stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running and make sure the electric
cooling fan is operating. If it is not,
turn the ignition off.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
3. Look for obvious coolant leaks from the
radiator, hoses,and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the coolant is leaking, stop the en-
gine immediately. Call your authorized
Toyota CNG dealer for assistance.
5. If there are no obvious leaks, check
the coolant reservoir. If it is dry, add
coolant to the reservoir while the en-
gine is running. Fill it about half full.
CAUTION
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.
6. After the engine coolant temperature
has cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You should have it checked as
soon as possible at your authorized
Toyota CNG dealer.
If your vehicle overheats
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IN THE 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 Chapter 7−3 for additional in-
formation.
Engine coolant level
Make sure the coolant level is between
the “FULL” and “LOW” lines on the see−
through reservoir when the engine is cold.
See Chapter 7−2 for additional information.
Battery electrolyte level
Make sure the electrolyte level of all bat-
tery cells is between upper and lower lev-
el lines on the case. Add only distilled
water when replenishing. See Chapter 7−3
for additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See Chapter 7−2 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 Chapter 7−2 for addi-
tional 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 Chapter 7−2 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 immedi-
ately. (See engine exhaust cautions in
Part 2.)Be on the alert for changes in perfor-
mance, sounds, and visual tip−offs that
indicate service is needed. Some impor-
tant clues are as follows:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A leak under the vehicle (however, wa-
ter 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 im-
mediately.)
Flat−looking tire; 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 almost touches
floor; vehicle pulls to one side when
braking
Engine coolant temperature continually
higher than normal
Does your vehicle need
repairing?
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158
Engine compartment overview
1. Power steering fluid reservoir
2. Engine coolant reservoir
3. Engine oil filler cap
4. Engine oil level dipstick
5. Brake fluid reservoir
6. Fuse blocks
7. Battery
8. Electric cooling fans
9. Windshield washer fluid tank
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Look at the see−through coolant reser-
voir when the engine is cold. The cool-
ant level is satisfactory if it is between
the “FULL” and “LOW” lines on the
reservoir. If the level is low, add ethyl-
ene−glycol type coolant for a proper
corrosion protection of aluminum com-
ponents.
The coolant level in the reservoir will vary
with engine temperature. However, if the
level is on or below the “LOW” line, add
coolant. Bring the level up to the “FULL”
line.
Always use ethylene−glycol type coolant
for a proper corrosion protection of alumi-
num components. See information in the
next column.
If the coolant level drops within a short
time after replenishing, there may be a
leak in the system. Visually check the
radiator, hoses, radiator cap and drain
cock and water pump.
If you can find no leak, have your autho-
rized Toyota CNG dealer test the cap
pressure and check for leaks in the cool-
ing system.CAUTION
To prevent burning yourself, do not
remove the radiator cap when the en-
gine is hot.
Coolant type selection
Use of improper coolants may damage
your engine cooling system. Your coolant
must contain ethylene−glycol type coolant
for a proper corrosion protection of your
engine that contains aluminum
components. Use “TOYOTA Long Life
Coolant” or equivalent.
In addition to preventing freezing and
subsequent damage to the engine, this
type of coolant will also prevent corrosion.
Further supplemental inhibitors or additives
are neither needed nor recommended.
Read the coolant container for information
on freeze protection. Follow the manufac-
turer’s directions for how much to mix
with plain water (preferably demineralized
water or distilled water). The total capacity
of the cooling system is given in Part 8.We recommend to use 50% solution for
your Toyota, to provide protection down to
about −35C (−31F). When it is extreme-
ly cold, to provide protection down to
about −50°C (−58°F), 60% solution is rec-
ommended. Do not use more than 70%
solution for better coolant performance.NOTICE
Do not use alcohol type antifreeze or
plain water alone.
Checking the engine coolant
level