2004 PONTIAC GTO check engine

Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Maintenance Requirements
Notice:Maintenance intervals, checks, inspections,
replacement parts and recommended uids and
lubricants as prescribed in this manual are
necessary to keep your vehicle in good working
condition. Any damage caused by failure to follow
scheduled maintenance may not be covered by
warranty.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. All recommended maintenance is
important. Improper vehicle maintenance can even
affect the quality of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level of
emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good condition,
be sure to maintain your vehicle properly.
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If you want to get service information, seeService
Publications Ordering Information on page 7-11.
Owner Checks and Services on page 6-9tells you what
should be checked, when to check it and what you
can easily do to help keep your vehicle in good
condition.
The proper replacement parts, fluids and lubricants to
use are listed inRecommended Fluids and Lubricants
on page 6-13andNormal Maintenance Replacement
Parts on page 6-15. When your vehicle is serviced,
make sure these are used. All parts should be replaced
and all necessary repairs done before you or anyone
else drives the vehicle. We recommend the use of
genuine GM parts.
Scheduled Maintenance
When the CHANGE OIL SOON light comes on, it
means that service is required for your vehicle. Have
your vehicle serviced as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are
driving under the best conditions, the engine oil
life system may not indicate that vehicle service is
necessary for over a year. However, your engine oil and
filter must be changed at least once a year and at
this time the system must be reset. Your GM
Goodwrench dealer has GM-trained service technicians
who will perform this work using genuine GM parts
and reset the system.If the engine oil life system is ever reset accidentally,
you must service your vehicle within 3,000 miles
(5 000 km) since your last service. Remember to reset
the oil life system whenever the oil is changed. See
Engine Oil on page 5-13for information on the Engine
Oil Life System and resetting the system.
When the CHANGE OIL SOON light appears, certain
services, checks and inspections are required. Required
services are described in the following for
“MaintenanceI” and “MaintenanceII.” Generally, it is
recommended that your first service be MaintenanceI,
your second service be MaintenanceIIand that you
alternate MaintenanceIand MaintenanceIIthereafter.
However, in some cases, MaintenanceIImay be
required more often.
MaintenanceI— Use MaintenanceIif the light comes
on within ten months since vehicle was purchased or
MaintenanceIIwas performed.
MaintenanceII— Use MaintenanceIIif the previous
service performed was MaintenanceI. Always use
MaintenanceIIwhenever the light comes on ten months
or more since the last service or if the light has not
come on at all for one year.
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Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and filter. Reset oil life system. SeeEngine Oil on
page 5-13.An Emission Control Service.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner filter. If necessary, replace filter. SeeEngine Air
Cleaner/Filter on page 5-18.An Emission Control Service. See footnote †.••
Rotate tires and check inflation pressures and wear. SeeTires on page 5-51.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer fluid levels and add fluid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission fluid level and add fluid as needed. SeeRecommended
Fluids and Lubricants on page 6-13for what to use.•
Inspect throttle system.See footnote (g).•
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(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
-In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
-In hilly or mountainous terrain.
-When doing frequent trailer towing.
-Uses such as found in taxi, police or delivery
service.
-Uses such as high performance operation.
(i)Drain, flush and refill cooling system. See Engine
Coolant on page 5-25for what to use. Inspect hoses.
Clean radiator, condenser, pressure cap and filler neck.
Pressure test the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.Owner Checks and Services
These owner checks and services should be performed
at the intervals specified to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-13for further
details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
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Engine Coolant Level Check
Check the engine coolant level and add
DEX-COOL®coolant mixture if necessary. SeeEngine
Coolant on page 5-25for further details.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the windshield
washer tank and add the proper fluid if necessary.
At Least Once a Month
Tire Ination Check
Visually inspect your tires and make sure tires are
inflated to the correct pressures. Do not forget to
check your spare tire. SeeTires on page 5-51for
further details.
At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-23if
necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, contact
your GM Goodwrench dealer for service.
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Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-23if necessary.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the key to the ON position,
but do not start the engine. Without applying the
regular brake, try to move the shift lever out
of PARK (P) with normal effort. If the shift lever
moves out of PARK (P), contact your GM
Goodwrench dealer for service.
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
•With an automatic transmission, the key should turn
to LOCK only when the shift lever is in PARK (P).
The key should come out only in LOCK.
•With a manual transmission, the key should turn to
LOCK only when the shift lever is in reverse. The
key should come out only in LOCK.
Contact your GM Goodwrench dealer if service is
required.
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Parking Brake and Automatic
Transmission Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
•To check the parking brake’s holding ability: With
the engine running and transaxle in NEUTRAL (N),
slowly remove foot pressure from the regular
brake pedal. Do this until the vehicle is held by the
parking brake only.
•To check the PARK (P) mechanism’s holding
ability: With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Contact your GM Goodwrench dealer if service is
required.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
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Vehicle Data Collection and Event
Data Recorders
Your vehicle, like other modern motor vehicles, has a
number of sophisticated computer systems that monitor
and control several aspects of the vehicle’s
performance. Your vehicle uses on-board vehicle
computers to monitor emission control components to
optimize fuel economy, to monitor conditions for air bag
deployment and, if so equipped, to provide anti-lock
braking and to help the driver control the vehicle
in difficult driving situations. Some information may be
stored during regular operations to facilitate repair
of detected malfunctions; other information is stored only
in a crash or near crash event by computer systems
commonly called event data recorders (EDR).
In a crash or near crash event, computer systems, such
as the Air Bag Sensing and Diagnostic Module (SDM)
in your vehicle may record information about the
condition of the vehicle and how it was operated, such
as engine speed, brake applications, throttle position,
vehicle speed, safety belt usage, air bag readiness, air
bag performance data, and the severity of a collision.
This information has been used to improve vehicle crash
performance and may be used to improve crash
performance of future vehicles and driving safety. Unlike
the data recorders on many airplanes, these on-board
systems do not record sounds, such as conversation of
vehicle occupants.To read this information, special equipment is needed
and access to the vehicle or the SDM is required.
GM will not access information about a crash event or
share it with others other than•with the consent of the vehicle owner or, if the
vehicle is leased, with the consent of the lessee,
•in response to an official request of police or similar
government office,
•as part of GM’s defense of litigation through the
discovery process, or
•as required by law.
In addition, once GM collects or receives data, GM may
•use the data for GM research needs,
•make it available for research where appropriate
confidentiality is to be maintained and need is
shown, or
•share summary data which is not tied to a specific
vehicle with non-GM organizations for research
purposes.
Others, such as law enforcement, may have access to
the special equipment that can read the information
if they have access to the vehicle or SDM.
If your vehicle is equipped with OnStar
®, please check
the OnStar®subscription service agreement or
manual for information on its operations and data
collection.
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