2004 GMC SAVANA engine

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the Check
Engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
Oil Pressure Gage
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate pressure in kPa
(kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.United States
Canada
3-37

A reading in the low pressure zone may be caused by a
dangerously low oil level or other problem causing
low oil pressure. Check your oil as soon as possible.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
Change Engine Oil Light
This light is displayed
when the engine oil needs
to be changed.
If your vehicle has a V8 engine and this light is ashing,
it indicates that the oil level is low.
When this light is on steady, it indicates the oil needs to
be changed soon.
Once the engine oil has been changed, the change
engine oil light must be reset. Until it is reset, the light
will be displayed when the engine is on. For more
information on resetting the system, seeEngine Oil on
page 5-11.
3-38

Security Light
The light will stay on until the engine starts. If the light
ashes, the Passlock®System has entered a tamper
mode. If the vehicle fails to start, seePasslock®
on page 2-20.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
System. Your vehicle will not be protected by Passlock®,
and you should see your GM dealer.
Cruise Control Light
The cruise light comes on whenever you set your cruise
control. See “Cruise Control” underTurn
Signal/Multifunction Lever on page 3-8. United States
CanadaUnited StatesCanada
3-39

Reduced Engine Power Light
If the check engine and
reduced engine power
lights are on, the throttle
may be disabled, and
a noticeable reduction in
the vehicle’s performance
may occur.
If the reduced engine power light is on, but there is no
reduction in performance, proceed to your destination.
The performance may be reduced the next time
the vehicle is driven. The vehicle may be driven at a
reduced speed while the reduced engine power light is
on, but acceleration and speed may be reduced.
Anytime the check engine light stays on, the vehicle
should be taken to an authorized GM dealer as soon as
possible for service.
Daytime Running Lamps
Indicator Light
You have this light on the
instrument panel. It will
light whenever the DRL are
on. It is also a reminder
to turn on your headlamps
when driving at night.
Tow/Haul Mode Light
This message is displayed
when the tow/haul mode
has been activated.
For more information, see “Tow/Haul Mode” inTowing a
Trailer on page 4-37.
3-40

Check Gages Warning Light
This light will come on briey when you are starting the
engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil
pressure gages to see if they are in the warning zones.
Fuel Gage
The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible. United States
Canada
United StatesCanada
3-41

Listed are four situations you may experience with your
fuel gage:
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity to ll the tank.
The gage moves a little when you turn a corner or
speed up.
The gage doesn’t go back to empty when you turn
off the ignition.
None of these indicate a problem with the fuel gage.
Audio System(s)
Notice:Before you add any sound equipment to
your vehicle – like a tape player, CB radio, mobile
telephone or two-way radio – be sure you can
add what you want. If you can, it’s very important to
do it properly. Added sound equipment may
interfere with the operation of your vehicle’s engine,
radio or other systems, and even damage them.
Your vehicle’s systems may interfere with the
operation of sound equipment that has been added
improperly.
So, before adding sound equipment, check with
your dealer and be sure to check federal rules
covering mobile radio and telephone units.
Your audio system has been designed to operate easily
and to give years of listening pleasure. You will get
the most enjoyment out of it if you acquaint yourself with
it rst. Figure out which radio you have in your vehicle,
nd out what your audio system can do and how to
operate all of its controls to be sure you’re getting the
most out of the advanced engineering that went into it.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, you can play your audio
system even after the ignition is turned off. See
“Retained Accessory Power (RAP)” underIgnition
Positions on page 2-21.
3-42

Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-29.
4-7

The following chart describes the Stabilitrak®Not Ready Light and the Stabilitrak®Indicator Light.
Stabilitrak®Not Ready Light Stabilitrak®Indicator Light Meaning
Off Off Stabilitrak®is enabled, but not active.
Off Flashing Stabilitrak®is enabled and active.
On Off Stabilitrak®is disabled.
On/Off On Vehicle needs to be serviced.
For more information, seeStabilitrak
®Not Ready Light
on page 3-33andStabilitrak®Indicator Light on
page 3-33.
Stabilitrak
®and part of the
traction control system can
be turned off or back on
by pressing the
Stabilitrak
®button located
on the instrument panel.
When the Stabilitrak
®system has been turned off you
may still hear system noises as a result of the
brake-traction control coming on.It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn
the system off if your vehicle is stuck in sand, mud, ice
or snow, and you want to “rock” your vehicle to
attempt to free it.
Traction Control Operation
The traction control system is part of the
Stabilitrak®system. Traction control limits wheel spin by
reducing engine power to the wheels (engine speed
management) and by applying brakes to each individual
wheel (brake-traction control) as necessary.
Notice:
Allowing the wheel of one axle to spin
excessively while the STABILITRAK NOT READY light
is on due to heavy braking and/or because the
traction control system has been continuously active,
may cause damage to the transfer case. This could
lead to costly repairs not covered by your warranty. Do
not allow the wheel of one axle to spin excessively
while the STABILITRAK NOT READY light is on.
4-10