fuel GMC ENVOY 1998 Owner's Manual

You can be injured and your vehicle could be
damaged if you try to do service work on
a
vehicle without knowing enough about it.
0 Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
0 Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused.
If you use
the wrong fasteners, parts can later break
or
fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around
it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Use regular unleaded gasoline rated at 87 octane or
higher. At a minimum,
it should meet specifications
ASTM D48 14
in the United States and CGSB 3.5-M93
in Canada. Improved gasoline specifications have been
developed by the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting the AAMA
specification could provide improved driveability and
emission control system protection compared
to
other gasolines.
Be SUI-e 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
LIP 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.
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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 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
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.
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.
I 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.
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Fuels in Foreign Countries
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
L1H 8P7
Filling Your Tank
The fuel cap is behind a hinged door on the driver’s side
of your vehicle.
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- , . . .. . , .. , . . . . . . . .
Gasoline vapor is highly flammable. It burns
violently, and that can cause very bad injuries.
Don’t smoke if you’re near gasoline or refueling
your vehicle. Keep sparks, flames and smoking
materials away from gasoline.
While refueling, hang the cap by the tether from the
hook on the filler door.
To remove the cap, turn it slowly to the left
(counterclockwise). The cap has a
spring in it; if you let
go of the cap too
soon, it will spring back to the right.
A CAUTION:
I
If you get gasoline on yourself and then
something ignites it, you could be badly burned.
Gasoline can spray out on you
if you open the
fuel filler cap too quickly. This spray can happen
if your tank
is nearly full, and is more likely in
hot weather. Open the fuel filler cap slowly and
wait for any “hiss” noise
to stop. Then unscrew
the cap all the way.
Be careful not to spill gasoline. Clean gasoline from
painted surfaces as soon as possible. See “Cleaning the
Outside
of Your Vehicle” in the Index.
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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. The diagnostic system
can determine if the fuel cap has been left off or
improperly installed. This would allow fuel to
evaporate into the atmosphere. See “Malfunction Indicator Lamp” in the Index.
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 properly. This may
cause your malfunction indicator lamp to light
and your fuel tank and emissions system may be
damaged. See “Malfunction Indicator Lamp” in
the Index.
Filling a Portable Fuel Container
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from the
container can ignite the gasoline vapor. You can
be badly burned and your vehicle damaged if this
occurs.
To help avoid injury to you and others:
Dispense gasoline only into
approved containers.
Do not fill a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or
on any surface other than the ground.
inside of the
fill opening before operating
the nozzle. Contact should be maintained
until the filling
is complete.
Bring the fill nozzle in contact with the
Don’t smoke while pumping gasoline.
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Remove the hood prop from the slot in the hood and
return the prop to its retainer.
Then just pull the hood down firmly
to close. It will
latch when dropped from 10 to12 inches (25 to 30 cm)
without pressing on the hood.
Engine Oil
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 oil
yellow dipstick is
a
ring.
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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What Kind of Eng 3il to Use
Oils recommended for your vehicle can be identified by
looking for the “Starburst” symbol. This symbol
indicates that the oil has been certified by the American
Petroleum Institute (API).
Do not use any oil which
does not carry this Starburst symbol.
If you change your own oil,
be sure you use oil that has
the Starburst symbol on the
front of the
oil container. If
you have your oil changed
for you, be sure the oil
put
into your engine is
American Petroleum
Institute certified
for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:
I RECOMMENDED SA€ VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
I SAL VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
L
HOT
WEATHER
+ 20 7
SAE SW-30 PREFERRED
LOOK
FOR MIS
SYMBOL
00 NOT USE SAE 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
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Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as
a result of too much friction.
You could have an air-out and
a serious
accident. See “Loading Your Vehicle” in
the Index.
Underinflated tires pose the same danger as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be cut,
punctured or broken by a sudden impact
--
such as when you hit a pothole. Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
Inflation -- Tire Pressure
The CertificatiodTire label, which is on the driver’s
door edge, above the door latch, shows the correct
inflation pressures for your tires when they’re cold.
“Cold” means your vehicle has been sitting for at least
three hours or driven no more than
1 mile (1.6 km).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right. It’s not.
If your tires
don’t have enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
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Finish Damage
Any stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer or other service
outlets. Larger areas
of finish damage can be corrected
in your dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody.
If these are not
removed, accelerated corrosion (rust) can occur
on
the underbody parts such as fuel lines, frame, floor
pan and exhaust system even though they have
corrosion protection.
At least every spring, flush these materials from the underbody with plain water. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create
a chemical fallout. Airborne pollutants can fall upon
and attack painted surfaces on your vehicle. This
damage can take two forms: blotchy, ringlet-shaped
discolorations, and small irregular dark spots etched into
the paint surface.
Although no defect in the paint job causes this,
GMC
will repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
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Name
RT TRN
RR PRK
TRL PRK
LT HDLP
RT HDLP
LT HI
RT HI
FR PRK
INT BAT
ENG
I
ECM B
ABS
ECM
1
HORN
BTS
I
BIU LP
IGN E
AIC
RAP
OXYSEN
Usage
Right Turn Signal Rear
Right Rear Parking Lamps
Trailer Park Lamps Left Headlamp
Right Headlamp
Left High Beam
Right High Beam
Front Parking Lamps
I/P Fuse Block Feed
Engine SensorsISolenoids, MAP,
CAM. PURGE, VENT
Engine Control Module, Fuel Pump,
Module, Oil Pressure
Anti-Lock Brake System
Engine Control Module Injectors Horn
Brake-Transmission Shift Interlock
Back-up
Lalllps
Engine
Air Conditioning
Retained Accessory Power
Oxygen Sensor
Name
IGN B
DRL
FOG LP
IGN
A
STUD #2
PARKLP
LR PRK
IGN C
HTDSEAT ATC
RRDFOG
HVAC
TRCHMSL
RR W/W
CRANK
LD LEV
HI BEAM
HAZLP
VECHMSL
HTDMIR
STOPLP
TBC
Usage
Column Feed, IGN 2, 3,4
Daytime Running Lamps
Fog Lamps
Starting and Charging IGN
I
Accessory Feeds, Electric Brake
Parking La~nps
Left Rear Parking Lamps Starter Solenoid, Fuel Pump. PRNDL
Heated Seat
Electronic Transfer Case
Rear Defogger
HVAC System
Trailer Center High Mount Stop Light
Rear Window Wiper
Clutch Switch, NSBU Switch
Electronic Load Leveling
HID Headlamps Hazard Lamps
Vehicle Center High
Mount Stop Lamp
Heated Mirror
Stoplamps
Truck Body Computer
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