check engine GMC SIERRA 1998 Owner's Manual

Be sure the posted octane is at least 87. If the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
hear heavy knocking, your engine needs service. But
don’t worry if you hear a little pinging noise when
you’re accelerating or driving
up a hill. That’s norlnal,
and you don’t have to
buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label),
it is designed to operate on fuels that meet
California specifications.
If such fuels are 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
on your instrument
panel may turn on and/or your
vehicle may fail
a smog-check test. If this occurs, return
to your authorized
GM dealer for diagnosis to determine
the cause
of’ fdilure. In the event it is determined that the
cause
of the condition is the type of fuels used, repairs
may not be covered by your warranty.
Some gasolines that are not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does not recommend the
use
of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator
lamp on your instrument panel
may
turn on. If this occurs, return to your authorized
GM dealer for service.
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To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent deposits from forming
in your engine and fuel
system, allowing your emission control system to
function properly. Therefore, you should
not have to add
anything to the fuel.
In addition, gasolines containing
oxygenates, such as ethers and ethanol, and
reformulated gasolines may be available
in your area to
help clean the air. General Motors recommends that
you
use these gasolines if they comply with the
specifications described earlier.
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don’t use
it. It can corrode
metal parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t
be covered under your warranty.
Fuels in Foreign COUI
(Gasoline Engines)
If you plan on driving in another country outside the
United States
or Canada, the proper fuel may be hard to
find. Never use leaded gasoline or any other fuel not
recommended
in the previous text on fuel. Costly repairs
caused by use of improper fuel wouldn’t be covered by
your warranty.
To check on fuel availability, ask an auto club, or
contact
a major oil company that does business in the
country where you’ll be driving.
You can also write us at the following address for
advice. Just tell us where you’re going and give your
Vehicle Identification Number
(VIN).
General Motors Overseas Distribution Corporation
1908 Colonel Sam Drive
Oshawa. Ontario
L 1 H 8P7
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Checking Things Under the Hood
I I A CAUTION:
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
I
A CAUTION:
I
I
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline or
diesel fuel, oil, coolant, brake fluid, windshield
washer and other fluids, and plastic or rubber.
You or others could be burned. Be careful not
to drop or spill things that
will burn onto a
hot engine.
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Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine Oil
(Diesel Engine)” in the Diesel Engine Supplement.
It’s
a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the
oil must
be warm and the vehicle
must be on level ground.
.. ..
The engine oil dipstick has a yellow ring handle and is
located
on the passenger’s side of the engine.
Turn
off the engine and give the oil a few minutes to
drain back into
the oil pan. If you don’t, the oil dipstick
might not show the actual
level.
Checking Engine Oil
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
u
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The air cleaner assembly
has an indicator that lets
you know when the air filter
is dirty and needs to be
serviced. The indicator is
located
in the air intake tube
between the air cleaner and
the engine.
See “Owner Checks and Services’’ 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.
To remove the air filter, unhook the retaining clips and
remove the cover. Lift the filter and the connected duct
out
of the air cleaner housing. Hold the duct and remove
the filter by both pulling and twisting the filter away
from the duct. Care should be taken to dislodge as little
dirt as possible.
Clean the filter sealing surface of the duct and
the
filter housing.
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Install the new filter by pushing it all the way to the stop
on the duct.
Install the duct and the filter into the air cleaner housing.
Make sure that the duct fits properly into the housing.
Install the cover and fasten the two retaining clips.
After the air filter
is properly serviced, the indicator
should be reset. Push the button on top
of the indicator
to reset it to the green (clean) filter
zone.
Refer to the Maintenance Schedule to determine when to
replace the air filter. See “Owner Checks and Services”
in the Index.
A CAUTION:
Operating the engine with the air cleaner 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 off.
I NOTICE:
If the air cleaner 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 in place when you’re driving.
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Automatic Transmission Fluid
If your vehicle has a diesel engine, see “Automatic
Transmission Fluid”
in the Diesel Supplement.
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83
000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
regularly
reaches
90°F (32°C) or higher.
If your vehicle’s GVWR is not over 8,600 and you do not
use your vehicle under any
of these conditions, change the
fluid and filter every
100,000 miles (166 000 km).
See “Scheduled Maintenance Services’’ in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your
GM 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 fluid can damage your
transmission.
Too much can mean that some of
the fluid could come
out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic -- especially in hot weather.
While pulling a trailer.
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). See “Checking Transmission Fluid Hot“ in
the Index.
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Checking Transmission Fluid Hot
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it's colder than
50°F (IOOC), drive the
vehicle in THIRD
(3) until the engine temperature gage
moves and then remains steady for 10 minutes. Then
follow
the hot check procedures.
Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting
for eight hours or more with the engine off and 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's colder than 50°F ( 1 O"C), you may have
to idle the engine longer. Should the fluid level be low
during
a cold check, you must perform a hot check
before adding fluid. This will give you
a more accurate
reading of the fluid level.
Checking the Fluid Hot or Cold
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:
1. The red transmission dipstick handle is located at the
rear
of the engine compartment, on the passenger's
side. Flip the handle up and then
pull out the dipstick
and wipe
it with a clean rag or paper towel.
then pull it back out again.
2. Push it back in all the way, wait three seconds and
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Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
changed. However, the fluid in your manual
transmission doesn’t require changing.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your GM dealership
Service Department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a fdse reading.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
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:
I. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of
the filler plug hole.
3. If the fluid level is good, install the plug and be sure
it is fully seated. If the fluid level is low, add more
fluid as described in the next steps.
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How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12
mrn) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
~
to remain in your vehicle for 5 years or 150,000 miles I
(240 000 km) whichever occurs first, if you add only ~
DEX-COOL’ extended life coolant.
8
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
i
with engine overheating, see “Engine Overheating” in 1
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant will: 1
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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