engine GMC ENVOY 1998 Workshop Manual

9. Attach the cable at least
18 inches (45 cm) away
from the dead battery,
but not near engine parts
that move.
The electrical
1 connection is just as
good there, but the
chance
of sparks getting
back to the battery
is
much less.
10. Now start the vehicle with the good battery and run
the engine for awhile.
12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
1 1. Try to start the vehicle with the dead battery. If it
won’t start after a few tries, make sure all
connections are good. If it still won’t start, it
probably needs service.
A.
R
I A CAUL3N:
u.
I c-
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine
is running.
Heavy Metal Engine Part
Good Battery
Dead Battery
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Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See "Gages" in the Index.
If Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you
badly, even if you ,just open the hood. Stay
away
from the engine if you see or hear steam coming
from
it. Just turn it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is
cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged.
The costly repairs would not be
covered
by your warranty.
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io Stea 5 Coming From Your Engine
~i you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get
a little too hot when you:
0 Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” in the Index.
If you get the overheat.warning with no sign of steam,
try this for a minute or
so:
1. Turn off your air conditioner.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- DRIVE (D) or THIRD (3).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, push the accelerator until
the engine speed is about twice as fast as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes.
Now see if the warning stops.
But then, if you still have the warning, turn ojfthe
engine nnd
get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
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When you decide it's safe to lift the hood, here's what
you'
I I see:
If the coolant inside the coolant recovery tank is boiling,
don't do anything else
until it cools down.
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan
c.
I
The coolant level should be at least up to the
ADD mark.
If it isn't, you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere else
in
the cooling system.
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1 h CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you
do, you can be burned.
Don’t run the engine if there is a leak.
If you run
the engine,
it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
NOTICE: I
Engine damage from running your engine
without coolant isn’t covered by your
1 warranty.
If there seems to be no leak, start the engine again. See
if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off
the engine.
How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t
at the ADD mark, add a 50/50 mixture of clean
brater (preferably distilled) and DEX-COOL@ engine
coolant at the coolant recovery tank. (See “Engine
Coolant”
in the Index for more information.)
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water
or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use a
50/50 mixture of clean water and
DEX-COOL@ coolant.
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NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
A CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at the
ADD r&ark, start your vehicle.
If the overheat warning continues, there’s one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling system is cool before you do
it.
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3. Fill the radiator with the proper DEX-COOL@
coolant mixture, up to the base of the filler neck.
(See "Engine Coolant"
in the Index for more
information about the proper coolant mixture.)
4. Then fill the coolant recovery tank to the ADD mark.
5. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.
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.. ..
6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower.
If the level is lower, add
more of
the proper DEX-COOL@ coolant mixture
through the filler neck until the level reaches the
base of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure
if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure the
arrows on the pressure
cap line up like this.
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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the clutch is
not engaged. This improves fuel economy and
reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the fan speed
increases when the clutch engages.
So you may hear an
increase in fan noise. This is normal and should not be
mistaken
as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may
also hear this fan noise when you start the
engine. It will go away
as the fan clutch disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly.
If air goes
out of
a tire, it’s much more likely to leak out slowly.
But
if you should ever have a “blowout,” here are a few
tips about what to expect and what to do:
If
a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side.
Take your foot off the
accelerator pedal and grip
the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the
way you want the vehicle to go. It may be
very bumpy and noisy, but you can
still steer. Gently
brake to
a stop -- well off the road if possible.
If a tire goes flat, the next part shows how to use your
iacking equipment to change
a flat tire safely. u Y a. c
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Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on
your hazard
warning flashers.
A CAUTION:
I
Changing a tire can cause an injury. The vdcle
can slip
off the jack and roll over you or other
people. You and they could be badly injured.
Find a level place to change your tire. To help
prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put the shift lever in PARK (P).
3. lbrn off the engine.
4. Put the wheel blocks at the front and
rear of the tire farthest away from the
one being changed. That would be the
tire on the other side of the vehicle,
at
the opposite end.
The following steps will tell you how to use the jack and
change a tire.
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