2008 PONTIAC G8 engine overheat

Notice:If the air cleaner/lter is
off, a backre can cause a
damaging engine re. And, dirt
can easily get into your engine,
which will damage it. Always have
the air cleaner/lter in place
when you are driving.
Automatic Transmission
Fluid
It is not necessary to check the
transmission uid level. A
transmission uid leak is the only
reason for uid loss. If a leak occurs,
take your vehicle to a dealer/retailer
and have it repaired as soon as
possible.
Change the uid and lter at the
intervals listed in the Maintenance
Schedule. SeeScheduled
Maintenance on page 11-4. Be sure
to use the transmission uid
listed inRecommended Fluids and
Lubricants on page 11-12.Notice:Use of the incorrect
automatic transmission uid may
damage your vehicle, and the
damages may not be covered by
your warranty. Always use the
automatic transmission uid
listed inRecommended Fluids
and Lubricants on page 11-12.
Engine Coolant
The cooling system in your vehicle is
lled with DEX-COOL®engine
coolant. This coolant is designed to
remain in your vehicle for ve years
or 150,000 miles (240 000 km),
whichever occurs rst, if you add
only DEX-COOL
®extended life
coolant.
The following explains your cooling
system and how to add coolant
when it is low. If you have a problem
with engine overheating, see
Engine Overheating on page 9-16.A 50/50 mixture of clean, drinkable
water and DEX-COOL
®coolant will:
Give freezing protection down
to−34°F (−37°C).
Give boiling protection up to
265°F (129°C).
Protect against rust and
corrosion.
Help keep the proper engine
temperature.
Let the warning lights and gages
work as they should.
Notice:Using coolant other than
DEX-COOL
®can cause premature
engine, heater core, or radiator
corrosion. In addition, the engine
coolant may require changing
sooner, at the rst maintenance
service after each 30,000 miles
(50 000 km) or 24 months,
whichever occurs rst. Any
repairs would not be covered by
the vehicle warranty. Always
use DEX-COOL
®(silicate-free)
coolant in the vehicle.
Vehicle Service and Care 9-13
2008 - Pontiac G8 Owner Manual

What to Use
Use a mixture of one-half clean,
drinkable water and one-half
DEX-COOL
®coolant which will not
damage aluminum parts. If you
use this coolant mixture, you do not
need to add anything else.
{CAUTION
Adding only plain water to the
cooling system can be
dangerous. Plain water, or
some other liquid such as
alcohol, can boil before the
proper coolant mixture will.
(Continued)
CAUTION (Continued)
The vehicle’s coolant warning
system is set for the proper
coolant mixture. With plain
water or the wrong mixture, the
engine could get too hot but
would not get the overheat
warning. The engine could
catch re and you or others
could be burned. Use a 50/50
mixture of clean, drinkable
water and DEX-COOL
®coolant.
Notice:If an improper coolant
mixture is used, the engine could
overheat and be badly damaged.
The repair cost would not be
covered by the vehicle warranty.
Too much water in the mixture
can freeze and crack the engine,
radiator, heater core, and
other parts.If you have to add coolant more
than four times a year, have
your dealer/retailer check your
cooling system.
Notice:If you use extra
inhibitors and/or additives in your
vehicle’s cooling system, you
could damage your vehicle. Use
only the proper mixture of the
engine coolant listed in this
manual for the cooling system.
SeeRecommended Fluids
and Lubricants on page 11-12for
more information.
9-14 Vehicle Service and Care
2008 - Pontiac G8 Owner Manual

Checking Coolant
The coolant reservoir and dipstick is
located in the engine compartment
on the passenger side of the vehicle.
SeeEngine Compartment Overview
on page 9-6for more information
on location.
1. Turn off the ignition.
2. Turn the coolant dipstick
cap one-eighth of a turn
counterclockwise and slowly
pull the dipstick straight up.3. When the engine is cold, the
coolant level should be at or
above the Min mark on the
dipstick.
After the vehicle has been driven
and the engine is at normal
operating temperature, the level
should be somewhere between
half full and the Max mark.
4. If the coolant level is correct,
replace the dipstick and turn
the cap one-eighth of a
turn clockwise.
Adding Coolant
If you need more coolant, add the
proper DEX-COOL
®coolant mixture
at the coolant reservoir, but only
when the engine is cool. If the
coolant reservoir is empty, a special
ll procedure is necessary. See
Engine Overheating on page 9-16
for instructions on “How to Add
Coolant to the Cooling System.”
{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.
Do not spill coolant on a hot
engine.
When replacing the coolant reservoir
cap, make sure it is hand-tight
and fully seated.
Radiator Pressure Cap
Notice:The radiator cap on your
vehicle is a pressure-type cap
and must be tightly installed
to prevent coolant loss and
possible engine damage from
overheating. Be sure the cap is
properly closed.
SeeEngine Compartment Overview
on page 9-6for more information
on location.
Vehicle Service and Care 9-15
2008 - Pontiac G8 Owner Manual

Engine Overheating
There is an engine coolant
temperature warning light on your
vehicle’s instrument panel. See
Engine Coolant Temperature Gage
on page 4-17.
If Steam Is Coming From Your
Engine
{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.
(Continued)
CAUTION (Continued)
If you keep driving when your
engine is overheated, the
liquids in it can catch re. 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 the engine catches re
because of being driven with
no coolant, your vehicle can be
badly damaged. The costly
repairs would not be covered by
the vehicle warranty.
If No Steam Is Coming From
Your Engine
An engine coolant temperature
warning can indicate a serious
problem. SeeEngine Coolant
Temperature Gage on page 4-17.If you get an engine coolant
temperature 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:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
If you get the engine coolant
temperature warning with no sign of
steam, try this for a minute or so:
1. If your air conditioner is on, turn
it off.
2. In heavy traffic, let the engine idle
in N (Neutral) while stopped. If it
is safe to do so, pull off the road,
shift to P (Park) or N (Neutral) and
let the engine idle.
3. Turn on your heater to full hot at
the highest fan speed and open
the windows as necessary.
9-16 Vehicle Service and Care
2008 - Pontiac G8 Owner Manual

If you no longer have the overheat
warning, you can drive. Just to
be safe, drive slower for about
10 minutes. If the warning does not
come back on, you can drive
normally.
If the warning continues and you
have not stopped, pull over, stop,
and park your vehicle right away.
If there is still no sign of steam, you
can idle the engine for three minutes
while you are parked. If you still have
the warning, turn off the engine and
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.Cooling System
When you decide it is safe to lift the hood, this is what you see:
A. Coolant Reservoir and Dipstick
B. Radiator Pressure CapV6 Engine
Vehicle Service and Care 9-17
2008 - Pontiac G8 Owner Manual

{CAUTION
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you
do, you can be burned.
Do not run the engine if there is
a leak. If you run the engine, it
could lose all coolant. That
could cause an engine re, and
you could be burned. Get any
leak xed before you drive the
vehicle.
If there seems to be no leak, with the
engine on, check to see if the electric
engine cooling fans are running.
If the engine is overheating, both
fans should be running. If they are
not, your vehicle needs service.
Notice:Engine damage from
running the engine without
coolant is not covered by the
warranty.Notice:Using coolant other than
DEX-COOL
®can cause premature
engine, heater core, or radiator
corrosion. In addition, the engine
coolant could require changing
sooner, at 30,000 miles
(50 000 km) or 24 months,
whichever occurs rst. Any
repairs would not be covered by
the vehicle warranty. Always
use DEX-COOL
®(silicate-free)
coolant in the vehicle.
How to Add Coolant to the
Cooling System
Notice:This vehicle has a
specic coolant ll procedure.
Failure to follow this procedure
could cause the engine to
overheat and be severely
damaged.If no coolant is visible in the coolant
reservoir, add coolant as follows:
{CAUTION
Adding only plain water to the
cooling system can be
dangerous. Plain water, or
some other liquid such as
alcohol, can boil before the
proper coolant mixture will.
The vehicle’s coolant warning
system is set for the proper
coolant mixture. With plain
water or the wrong mixture, the
engine could get too hot but
you would not get the overheat
warning. The engine could
catch re and you or others
could be burned. Use a 50/50
mixture of clean, drinkable
water and DEX-COOL
®coolant.
Vehicle Service and Care 9-19
2008 - Pontiac G8 Owner Manual

Turn Signals When Towing a
Trailer
When you tow a trailer, your vehicle
may need a different turn signal
asher and/or extra wiring. Check
with your dealer/retailer. The arrows
on your instrument panel will
ash whenever you signal a turn or
lane change. Properly hooked
up, the trailer lamps will also ash,
telling other drivers you are
about to turn, change lanes or stop.
When towing a trailer, the arrows
on your instrument panel will
ash for turns even if the bulbs on
the trailer are burned out. Thus, you
may think drivers behind you are
seeing your signal when they
are not. It is important to check
occasionally to be sure the trailer
bulbs are still working.
Your vehicle has bulb warning
lights. When you plug a trailer
lighting system into your vehicle’s
lighting system, its bulb warning
lights may not let you know if one of
your lamps goes out. So, whenyou have a trailer lighting system
plugged in, be sure to check
your vehicle and trailer lamps from
time to time to be sure they are
all working. Once you disconnect the
trailer lamps, the bulb warning
lights again can tell you if one of
your vehicle lamps is out.
Driving On Grades
Reduce speed and shift to a lower
gearbeforeyou start down a
long or steep downgrade. If you do
not shift down, you might have
to use your brakes so much
that they would get hot and no
longer work well.
On a long uphill grade, shift down to
a lower gear and reduce your
speed to around 45 mph (70 km/h)
to reduce the possibility of engine
and transmission overheating.
Parking on Hills
{CAUTION
You really should not park your
vehicle, with a trailer attached,
on a hill. If something goes
wrong, your rig could start to
move. People can be injured,
and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig
on a hill, here is how to do it:
1. Apply your regular brakes, but do
not shift into P (Park) yet.
2. Have someone place chocks
under the trailer wheels.
3. When the wheel chocks are in
place, release the regular
brakes until the chocks absorb
the load.
4. Reapply the regular brakes.
Then apply your parking
brake, and then shift to P (Park).
5. Release the regular brakes.
9-90 Vehicle Service and Care
2008 - Pontiac G8 Owner Manual

When You Are Ready to Leave
After Parking on a Hill
1. Apply your regular brakes and
hold the pedal down while you:
Start your engine.
Shift into a gear.
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is
clear of the chocks.
4. Stop and have someone pick up
and store the chocks.
Maintenance When Trailer
Towing
Your vehicle will need service more
often when you’re pulling a trailer.
See the Maintenance Schedule for
more on this. Things that are
especially important in trailer
operation are automatic transmission
uid (don’t overll), engine oil, drivebelt, cooling system and brake
system. Each of these is covered in
this manual, and the Index will help
you nd them quickly. If you’re
trailering, it’s a good idea to review
this information before you start
your trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
Your cooling system may
temporarily overheat during severe
operating conditions. SeeEngine
Overheating on page 9-16.
Appearance Care
Interior Cleaning
Your vehicle’s interior will continue
to look its best if it is cleaned
often. Although not always visible,
dust and dirt can accumulate
on your upholstery. Dirt can damage
carpet, fabric, leather, and plastic
surfaces. Regular vacuuming
is recommended to remove particles
from the upholstery. It is important
to keep your upholstery from
becoming and remaining heavily
soiled. Soils should be removed as
quickly as possible. Your vehicle’s
interior may experience extremes of
heat that could cause stains to
set rapidly.
Lighter colored interiors may require
more frequent cleaning. Use care
because newspapers and garments
that transfer color to your home
furnishings may also transfer color
to your vehicle’s interior.
Vehicle Service and Care 9-91
2008 - Pontiac G8 Owner Manual