engine PONTIAC GTO 2005 Repair Manual

{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned. The
air cleaner not only cleans the air; it helps to
stop ame if the engine backres. If it is not
there and the engine backres, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.
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
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission fluid listed inRecommended
Fluids and Lubricants on page 6-12.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
part or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving in the
following conditions:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
To get the right reading, the fluid should be at
normal operating temperature, which is 180°F to
200°F (82°C to 93°C).
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Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is colder than 50°F (10°C), drive the vehicle
in DRIVE (D) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold fluid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle for five minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 50°F (10°C), you
may have to idle the engine longer. Should the fluid
level be low during this cold check, you must check the
fluid hot before adding fluid. Checking the fluid hot
will give you a more accurate reading of the fluid level.
Checking the Fluid Level
Prepare your vehicle as follows:
•Park your vehicle on a level place. Keep the
engine running.
•With the parking brake applied, place the shift lever
in PARK (P).
•With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
•Let the engine run at idle for three minutes or more.Then, without shutting off the engine, follow
these steps:
The automatic transmission dipstick is located at the
rear of the engine compartment, on the passenger’s side
of the vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location.
1. Unclip the handle and remove the dipstick; wipe it
clean with a clean rag or paper towel and re-insert
it fully. Remove it again and read the fluid level.
2. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for
a cold check or in the cross-hatched HOT area
for a hot check.
3. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
Remember to always replace the dipstick and lock
the handle down.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants on page 6-12.
Add fluid only after checking the transmission fluid while
it is hot. A cold check is used only as a reference. If
the fluid level is low, add only enough of the proper fluid
to bring the level up to the HOT area for a hot check.
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The level should never read over the HOT mark, so be
careful not to add too much. It does not take much
fluid, generally less than 0.6 pints (0.3 L). Do not overfill.
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 in
Recommended Fluids and Lubricants on page 6-12.
•After adding fluid, recheck the fluid level as
described under “How to Check,” earlier in
this section.
•When the correct fluid level is obtained, push the
dipstick back in all the way.
Remember to always replace the dipstick and lock
the handle down.
•If fluid has to be added often, there may be a
problem or leak and you should see your dealer.
Manual Transmission Fluid
When to Check
A good time to have your manual transmission fluid
checked is when the engine oil is changed. However,
the fluid in your manual transmission does not
require changing.
How to Check
Because this operation can be difficult, you may choose
to have this done at your dealership service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
part or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.
Check the fluid level only when your engine is off, the
vehicle is parked on a level place and the transmission
is cool enough for you to rest your fingers on the
transmission case.
Then, follow these steps:
1. Remove the reverse light switch.
2. Check that the lubricant level is up to the bottom of
the switch hole.
3. If the fluid level is good, install the switch and be
sure it is fully seated. If the fluid level is low, add
more fluid as described in the next steps.
5-21

How to Check and Add Fluid
To check the fluid level, look at the markings on the
reservoir. If the fluid level is between the MIN and the
MAX line, the fluid level is correct. If the fluid level
is between these marks do not remove the cap, as the
fluid will quickly absorb moisture. SeeEngine
Compartment Overview on page 5-12for more
information on reservoir location.
If fluid does need to be added, first turn the vehicle off.
Remove the cap and add the proper fluid. Remember
to replace the cap and clean up any spilled fluid.
Engine Coolant
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first, if only
DEX-COOL
®extended life coolant is added.The following explains the cooling system and how to
add coolant when it is low. If there is a problem
with engine overheating or if coolant needs to be added
to the radiator, seeEngine Overheating on page 5-26.
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
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-23

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 this coolant mixture is used, nothing
else needs to be added.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as 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 would not get the overheat warning.
Your 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 you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.If coolant needs to be added more than four times a
year, have your dealer check the cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant overflow reservoir is located in the engine
compartment on the driver’s side of the vehicle. See
Engine Compartment Overview on page 5-12for more
information on location.
5-24

The coolant level should be checked at each fuel fill, by
looking at the dipstick in the coolant overflow reservoir.
To remove the dipstick, push down on the coolant
reservoir cap while turning it counterclockwise.
When your engine is cold, the coolant level should be at
or above the bottom arrow on the dipstick. After the
vehicle has been driven and the engine is at normal
operating temperature, the level should be somewhere
between the two arrows on the dipstick.
If the coolant level is correct, replace the dipstick then
push down on the coolant reservoir cap while turning
it clockwise until it stops, to lock it into position.
Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the coolant overflow reservoir, but
be careful not to spill it. Check the level with the dipstick
and keep adding fluid until the level is correct.
{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 the level is correct, replace the dipstick then push
down on the coolant reservoir cap while turning it
clockwise until it stops, to lock it into position.
5-25

If the coolant overflow reservoir is completely empty,
add coolant to the radiator. SeeEngine Overheating on
page 5-26.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator pressure
cap — even a little — when the engine and
radiator are hot.
Occasionally check the coolant in the radiator. For
information on how to add coolant to the radiator, see
Cooling System on page 5-29.
Radiator Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
SeeEngine Compartment Overview on page 5-12for
information on location.
Engine Overheating
Immediate action is required if your engine overheats.
This is indicated by the coolant temperature gage
and the Engine Temp Hot message on the trip computer
display. SeeEngine Coolant Temperature Gage on
page 3-28andTrip Computer on page 3-33for more
information.
5-26

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.
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 your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
If No Steam Is Coming From Your
Engine
An overheat warning, along with an Engine Temp Hot
message can indicate a serious problem.
If you get an engine 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:
•Climb a long hill on a hot day.
•Stop after high-speed driving.
•Idle for long periods in traffic.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
apply the parking brake, shift to PARK (P) or
NEUTRAL (N) and let the engine idle while you get
out and check that the cooling fan is working.
5-27

2. If the fan is working and the temperature gage
needle has not returned to its normal position
within a few minutes, stop the engine and remove
the ignition key.
Look for leaks at the radiator hoses and
connections, heater hoses and connections,
radiator, and water pump. Be careful when checking
these areas as they will probably still be hot. If
you find a major leak or other problems that may
have caused the engine to overheat, do not run the
engine until these problems have been corrected.
If you do not find anything wrong, you should check
the engine coolant level. SeeEngine Coolant on
page 5-23. You should also check the air intake
area below the front bumper to ensure that it is clear
of leaves and road grime.3. Turn off your air conditioning and turn on your
heater to full hot at the highest fan speed and
open the windows as necessary.
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.
5-28

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Radiator Pressure Cap
B. Electric Engine Cooling Fan
C. Engine Coolant Overflow Reservoir{CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If you can hear the coolant inside the coolant overflow
reservoir bubbling or boiling, do not do anything
else until it cools down. The vehicle should be parked
on a level surface.
5-29