1998 GMC ENVOY fuel

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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Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are
based on the latest information available at the time of
printing, and are subject
to change. If a part listed in this
manual is not the same as the part used in your vehicle
when it was built, or if you have any questions, please
contact your GMC dealer.
Thermostat
......................... 1255905 1
Oil Filter ............................... PF52
Air Cleaner Filter
...................... A1 163C
PCV Valve
.......................... CV746C
Automatic Transmission Filter Kit
...... 24200796
Spark Plugs
.......................... .41-932
Fuel Filter
............................. GF48 1
Front Windshield Wiper Blade
................ Trico (20 inched50.8 cm)
Backglass Wiper Blade . . Trico (14 inched35.6 cm)
Capacities (Approximate)
Cooling System* ............. 11.7 quarts (1 1.1 L)
Crankcase* ................... 4.5 quarts (4.3 L)
Automatic Transmission
(Drain and Refill)*
........... 5.0 quarts (4.7 L)
Differential Fluid ............................
Front ....................... 2.6 pints (1.2 L)
Rear ........................ 4.0 pints ( 1.9 L)
Fuel Tank ..................... 18 gallons (68 L)
A/C Refrigerant ........... 30 oz. or 2 lbs. (0.9 kg)
of R- 134a
*After refill, the level
must be checked.
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Part A: Scheduled Maintenance
Services
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good working condition. But we don’t
know
exactly how you’ll drive it. You may drive very short
distances
only a few times a week. Or you may drive
long distances all the time in very hot, dusty weather.
You may use
your vehicle in making deliveries. Or
you may drive
it to work, to do errands or in many
other ways.
Because
of all the different ways people use their
vehicles, maintenance needs vary. You may even need
more frequent checks and replacements than you’ll find
in the schedules in this section. So please read this
section and
note how you drive. If you have any
questions
on how to keep your vehicle in good
condition, see your dealer.
This part tells you the maintenance services you should
have done and
when you should schedule them. If you
go to your dealer for your service needs, you’ll know
that GM-trained and supported service people will
perform the work using genuine GM parts. The proper fluids and lubricants to use are listed in
Part D. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the vehicle.
These schedules are for vehicles that:
0 carry passengers and cargo within recommended
limits. You will find these limits on your vehicle’s
Certificationflire label. See “Loading Your Vehicle”
in the Index.
0 are driven on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner. See
“Off-Road Driving With Your Four-Wheel-Drive
Vehicle”
in the Index.
0 use the recommended fuel. See “Fuel” in the Index.
Selecting the Right Schedule
First you’ll need to decide which of the two schedules is
right for your vehicle. Here’s how to decide which
schedule to follow:
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