check engine CHEVROLET SUBURBAN 1997 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
still 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 normal,
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 tune-up 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 failure. 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
methylcyclopentadlenyl 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 Countries -- 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 International Product Center 1908 Colonel Sam Drive
Oshawa, Ontario
L1H 8P7
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When you put the cap back on, turn it to the right
(clockwise) until you hear a clicking sound.
Make sure
you fully install the cap.
NOTICE:
If you need a new cap, be sure to get the right
type. Your dealer can get one for you.
If you get
the wrong type, it may not
fit or have proper
venting, and your fuel tank and emissions system
might be damaged.
Checking Things Under the Hood
'
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.
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.
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.
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.
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Air Cleaner (Gasoline Engines)
Your air cleaner is located between the battery and
coolant recovery tank. 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.
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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
backfhes.
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.
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.
Automatic Transmission Fluid
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 is mainly driven under one or
more
of these conditions:
0 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.
0 Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these
conditions, the fluid and filter do not require changing.
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.
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If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
I 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:
0 When outside temperatures are above 90°F (32" C).
0 At high speed for quite a while.
0 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).
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 (lO"C), 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 (lO"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.
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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). Then, without shutting
off the engine, follow these steps:
Let the engine run at idle for three minutes or more.
1. The red transmission dipstick 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.
2. Push it back in all the way, wait three seconds and
then pull
it back out again.
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What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOLS coolant which
won’t damage aluminum parts.
If you use this mixture,
you don’t need to add anything else.
J
A CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will.
Your vehicle’s coolant warning
system is set
for the proper coolant mix. With
plain .water
or the wrong mix, your engine could
get too hot but you wouldn’t get the overheat
warning.
Your engine could catch fire and you or
others could be burned. Use a
50/50 mix of clean
water and
DEX-COOL@ coolant.
I NOTICE:
If’ you use an improper coolant mix, your engine
could overheat and be badly damaged. The repair
cost wouldn’t be covered by your warranty.
Too
much water in the mix can freeze and crack the
engine, radiator, heater core and other parts.
If you have to add coolant more than four times a year,
have
your dealer check your cooling system.
NOTICE:
~~ ~~
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
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Checking Coolant
The coolant recovery tank is located on the passenger’s
side at
the rear corner of the engine compartment.
When your engine is cold, the coolant level should be at
the
COLD mark, or a little higher. When your engine is
warm, the level should be up to the HOT mark, or a
little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture ut the coolant recovery tank.
-
A CAUTION:
I -
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids
to blow out and burn you badly.
With the coolant recovery tank, you will almost
never have to add coolant at the radiator.
Never turn the radiator pressure cap
-- even a
little -- when the engine and radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to spill
it.
A CAUTION:
W
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine.
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