Page 132 of 411

2-61 Malfunction Indicator Lamp (Service
Engine Soon Light in the United States
or Check Engine Light in Canada)
(4.3L, 5.0L & 5.7L Engines and
8.1L California Gasoline Engine)
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 or
CHECK ENGINE 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.
Page 136 of 411

2-65 Malfunction Indicator Lamp (Service
Engine Soon Light) (Check Engine Light)
(8.1L Gasoline Engine -- Except California)
United States Canada
If this light comes on or flashes while you are driving,
two things may happen.
First, you won't notice any difference in engine
performance, but your tail pipe emissions may increase.
Second, your engine may not run properly or may stall
without warning. If either of these things happen, drive
or tow your vehicle to your dealer for service.This light should come on when the ignition is on, but
the engine is not running, as a check to show you it is
working. If it does not come on at all, have it repaired.
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.
Reduced Engine Power
The REDUCED ENGINE
POWER light will come
on when the cooling system
temperature gets too hot
and the engine further
enters the engine coolant
protection mode.
See ªEngine Overheatingº in the Index for
further information.
Page 188 of 411

3-49
If your vehicle is equipped with the AM-FM Stereo
with Cassette Tape and Compact Disc Player with
Radio Data System and Programmable Equalization
do the following:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio off.
3. Press and hold the TAPE CD button for five seconds.
READY will appear on the display for five seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
When the cleaning cassette has been ejected, the broken
tape detection feature is active again.You may also choose a non-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to clean
the tape head. This type of cleaning cassette will not
eject on its own. A non
-scrubbing action cleaner may
not clean as thoroughly as the scrubbing type cleaner.
The use of a non
-scrubbing action, dry-type cleaning
cassette is not recommended.
After you clean the player, press and hold the cassette
eject symbol or the EJT button for five seconds to reset
the CLEAN or CLN indicator. The radio will display
CLEANED or
--- to show the indicator was reset.
Cassettes are subject to wear and the sound quality
may degrade over time. Always make sure the cassette
tape is in good condition before you have your tape
player serviced.
Page 271 of 411

6-4
In Canada, look for
the ªAuto Makers'
Choiceº label on
the pump.
Canada Only
California Fuel
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label), it is
designed to operate on fuels that meet California
specifications. If this fuel is not available in states adopting
California emissions standards, your vehicle will operate
satisfactorily on fuels meeting federal specifications, but
emission control system performance may be affected. The
malfunction indicator lamp may turn on (see ªMalfunction
Indicator Lampº in the Index) and your vehicle may fail a
smog
-check test. If this occurs, return to your authorizedGM dealer for diagnosis. If it is determined that the
condition is caused by the type of fuel used, repairs
may not be covered by your warranty.
Additives
Some gasolines that are not reformulated for low
emissions may contain an octane
-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may be
affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly.
You should not have to add anything to your fuel.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specifications described earlier.
Page 284 of 411
6-17
Engine Air Cleaner/Filter
(Gasoline Engines)
The engine air cleaner/filter is located near the center of
the engine compartment. See ªEngine Compartment
Overviewº in the Index for more information on location.
The engine air cleaner/filter
assembly has an indicator
that lets you know when the
air filter is dirty and needs
to be serviced. See ªOwner
Checks and Servicesº in the
Index to determine when to
check the indicator.
If the area inside the clear section of the indicator is
green, no air filter service is required. When the area
inside the indicator is orange and CHANGE AIR
FILTER appears, the filter should be replaced.
Page 285 of 411

6-18
To change the engine air cleaner/filter, do the following:
1. Unhook the retainer clips and remove the cover.
2. Lift the filter out of the engine air cleaner/filter
housing. Care should be taken to dislodge as little
dirt as possible.
3. Clean the engine air cleaner/filter housing.
4. Install the new engine air cleaner/filter into the
engine air cleaner/filter housing. Make sure that it
fits properly into the housing.
5. Install the cover and fasten the retaining clips.
6. After the engine air cleaner/filter is properly
serviced, the indicator should be reset. Push the
button on the top of the indicator to reset it to the
green (clean) filter zone.
See ªNormal Replacement Partsº for the proper filter
to use.
Refer to the Maintenance Schedule to determine when to
replace the engine air cleaner/filter and crankcase
ventilation filter. See ªScheduled Maintenance Servicesº
in the Index.
CAUTION:
Operating the engine with the air cleaner/filter
off can cause you or others to be burned. The air
cleaner not only cleans the air, it stops flame if
the engine backfires. If it isn't there, and the
engine backfires, you could be burned. Don't
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
NOTICE:
If the air cleaner/filter is off, a backfire can
cause a damaging engine fire. And, dirt can easily
get into your engine, which will damage it.
Always have the air cleaner/filter in place when
you're driving.
Page 299 of 411

6-32 Brake Wear
Your vehicle has front disc brakes and rear drum brakes.
Disc brake pads have built
-in wear indicators that
make a high
-pitched warning sound when the brake
pads are worn and new pads are needed. The sound may
come and go or be heard all the time your vehicle is
moving (except when you are pushing on the brake
pedal firmly).
CAUTION:
The brake wear warning sound means that soon
your brakes won't work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in the
proper sequence to GM torque specifications.
Your rear drum brakes don't have wear indicators, but if
you ever hear a rear brake rubbing noise, have the rear
brake linings inspected immediately. Also, the rear
brake drums should be removed and inspected each time
the tires are removed for rotation or changing. When
you have the front brake pads replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See ªBrake System Inspectionº in Section 7
of this manual under Part C ªPeriodic
Maintenance Inspections.º
Page 351 of 411

Short Trip/City Scheduled Maintenance
7-12
15,000 Miles (25 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)
Diesel Engine Only: Inspect engine air cleaner filter if you are driving in
dusty conditions. Replace filter if necessary.
An Emission Control Service. (See footnote .)
Gasoline Engine Only: See ªEngine Air Cleaner Filter Restriction Indicator
Checkº in the Index.
Check axle fluid level and add fluid as needed. 2500 and 3500 Series Only:
If driving in dusty areas or when towing a trailer, drain fluid and refill every
15,000 miles (25 000 km).
Clean and repack the front wheel bearings (or at each brake relining,
whichever occurs first).
Vehicles With GVWR Above 10,000 lbs. or Equipped with Diesel Engine
Only: Inspect shields for damage or looseness. Adjust or replace as required.
This is a Noise Emission Control Service. Applicable only to vehicles sold
in the United States.ACTUAL
SERVICED BY:MILEAGE
DATE