2000 GMC ENVOY engine

2-29
Engine Exhaust
CAUTION:
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you can't see or
smell. It can cause unconsciousness and death.
You might have exhaust coming in if:

Your exhaust system sounds strange
or different.

Your vehicle gets rusty underneath.

Your vehicle was damaged in a collision.

Your vehicle was damaged when driving over
high points on the road or over road debris.

Repairs weren't done correctly.

Your vehicle or exhaust system had been
modified improperly.
If you ever suspect exhaust is coming into
your vehicle:

Drive it only with all the windows down to
blow out any CO; and

Have your vehicle fixed immediately.
Running Your Engine While
You're Parked
It's better not to park with the engine running. But if
ever you have to, here are some things to know.
CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle (see the earlier Caution under
ªEngine Exhaustº).
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even if
the fan switch is at the highest setting. One place
this can happen is a garage. Exhaust
-- with
CO
-- can come in easily. NEVER park in a
garage with the engine running.
Another closed-in place can be a blizzard.
(See ªBlizzardº in the Index.)
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2-30
CAUTION:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
Don't leave your vehicle when the engine is
running unless you have to. If you've left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure your
vehicle won't move, even when you're on fairly
level ground, always set your parking brake and
move the shift lever to PARK (P).
Follow the proper steps to be sure your vehicle won't
move. See ªShifting Into PARK (P)º in the Index.
If you're pulling a trailer, see ªTowing a Trailerº in
the Index.
Locking Rear Axle
Your locking rear axle can give you additional traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when one of the rear
wheels has no traction and the other does, this feature
will allow the wheel with traction to move the vehicle.
Windows
Power Windows
The controls for the power windows are located on the
armrest of each of the side doors. The switches operate
the windows when the ignition is on, in ACCESSORY
or when Retained Accessory Power (RAP) is present.
(See ªRetained Accessory Powerº in the Index.)
The driver's door has a switch to control the passenger
windows as well.
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2-58 Programming the Transmitter
Do not use the HomeLink Transmitter with any garage
door opener that does not have the ªstop and reverseº
feature. This includes any garage door opener model
manufactured before April 1, 1982.
Be sure that people and objects are clear of the garage
door you are programming.
Your vehicle's engine should be turned off while
programming the transmitter. Follow these steps to
program up to three channels:
1. If you have previously programmed a transmitter
channel, proceed to Step 2. Otherwise, hold
down the two outside buttons on the HomeLink
Transmitter until the indicator light begins to flash
rapidly (after 20 seconds). Then release the buttons.
This procedure initializes the memory and erases any
previous settings for all three channels.
2. Decide which one of the three channels you want to
program. Hold the end of the hand
-held transmitter
about 2 to 5 inches (5 to 13 cm) away from the
surface of the HomeLink Transmitter so that you can
still see the indicator light.3. Using both hands, press the hand
-held transmitter
button and the desired button on the HomeLink
Transmitter. Continue to press both buttons
through Step 4.
4. Hold down both buttons until you see the red
light on the HomeLink Transmitter flash rapidly.
The rapid flashing indicates that the HomeLink
Transmitter has been programmed. Release both
buttons once the light starts to flash rapidly.
If you have trouble programming the HomeLink
Transmitter, make sure that you have followed the
directions exactly as described and that the battery in
the hand
-held transmitter is not dead. If you still cannot
program it, rotate the hand
-held transmitter end over end
and try again. The HomeLink Transmitter may not work
with older garage door openers that do not meet current
Federal Consumer Safety Standards. If you cannot
program the transmitter after repeated attempts, refer to
ªTraining a Garage Door Opener with Rolling Codesº
later in this section or contact the manufacturer of the
unit at 1
-800-355-3515.
Be sure to keep the original hand
-held transmitter
in case you need to erase and reprogram the
HomeLink Transmitter.
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2-63 Speedometer and Odometer
Your speedometer lets you see your speed in both miles
per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has been
driven, in either miles (used in the United States) or
kilometers (used in Canada).
The odometer mileage can be checked without the
vehicle running. Simply press the trip odometer button.
You may wonder what happens if your vehicle needs a
new odometer installed. If the new one can be set to the
mileage total of the old odometer, then it must be. But if
it can't, then it's set at zero, and a label must be put on
the driver's door to show the old mileage reading when
the new odometer was installed.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
To view the trip odometer, press the button near the
readout. To reset the trip odometer, hold the button
until it resets.
Tachometer
The tachometer displays the engine speed in revolutions
per minute (rpm).
The tachometer has three areas: normal operating range,
red warning range and red danger range.
The normal operating range shows your engine speed
during normal driving conditions. For example, when
the needle points to 2, it means the engine is running
at 2,000 revolutions per minute (rpm). The tachometer
needle will vary all the time that the engine is running.
The shaded red warning range tells you that your engine
speed is reaching its upper limits. Don't drive very long
with the tachometer in the red warning range. Lift your
foot off the accelerator pedal.
The solid red danger range tells you that your engine speed
is at its upper limits. You should immediately shift to a
higher gear, or lift your foot off the accelerator pedal.
NOTICE:
Do not operate the engine with the tachometer in
the red range, or engine damage will occur.
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2-64
Warning Lights, Gages and Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages and
warning lights work together to let you know when
there's a problem with your vehicle.When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for about eight seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for about 20 seconds,
then it will flash for
about 55 seconds.
If the driver's belt is already buckled, neither the chime
nor the light will come on.
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2-66 Charging System Indicator Light
The charging system light
will come on briefly when
you turn on the ignition,
but the engine is not
running, as a check to
show you it is working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system. It could indicate
that you have problems with a generator drive belt, or
another electrical problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition
is on (in RUN), this gage
shows your battery's state
of charge in DC volts.
When the engine is running, the gage shows the condition
of the charging system. Readings between the low and
high warning zones indicate the normal operating range.
Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
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2-68 Anti-Lock Brake System Warning Light
With the anti-lock brake
system, this light will
come on when you start
your engine and may stay
on for several seconds.
That's normal.
If the light stays on, or comes on when you're driving,
your vehicle needs service. If the regular brake system
warning light isn't on, you still have brakes, but you
don't have anti
-lock brakes. If the regular brake system
warning light is also on, you don't have anti
-lock brakes
and there's a problem with your regular brakes. See
ªBrake System Warning Lightº earlier in this section.
The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to RUN.
If the light doesn't come on then, have it fixed so it
will be ready to warn you if there is a problem.
Engine Coolant Temperature Gage
United States Canada
This gage shows the engine coolant temperature.
If the gage pointer moves into the red area, your engine
is too hot!
It means that your engine coolant has overheated.
If you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop
your vehicle and turn off the engine as soon as possible.
The ªProblems on the Roadº section of this manual
show you what to do. See ªEngine Overheatingº in
the Index.
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2-69 Malfunction Indicator Lamp
(Service Engine Soon Light)
United States Canada
Your vehicle is equipped with a computer which monitors
operation of the fuel, ignition and emission control systems.
This system is called OBD II (On
-Board
Diagnostics
-Second Generation) and is intended to
assure that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment. The SERVICE ENGINE SOON light
comes on to indicate that there is a problem and
service is required. Malfunctions often will be indicated
by the system before any problem is apparent. This
may prevent more serious damage to your vehicle.
This system is also designed to assist your service
technician in correctly diagnosing any malfunction.
NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be as
good and your engine may not run as smoothly.
This could lead to costly repairs that may not be
covered by your warranty.
NOTICE:
Modifications made to the engine, transmission,
exhaust or fuel system of your vehicle or the
replacement of the original tires with other than
those of the same Tire Performance Criteria
(TPC) can affect your vehicle's emission controls
and may cause the SERVICE ENGINE SOON
light to come on. Modifications to these systems
could lead to costly repairs not covered by your
warranty. This may also result in a failure to pass
a required Emission Inspection/Maintenance test.
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