Fuel system CHEVROLET EXPRESS 2002 User Guide

6-3
CAUTION:
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.

Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.

Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
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 (Gasoline Engine)
If your vehicle has a diesel engine, see ªDiesel Fuel
Requirements and Fuel Systemº in the Diesel Engine
Supplement. For vehicles with gasoline engines, please
read this.
Gasoline Octane
Use regular unleaded gasoline with a posted octane of
87 or higher. If the octane is less than 87, you may get
a heavy knocking noise when you drive. If it is bad
enough, it can damage your engine. A little pinging
noise when you accelerate or drive uphill is considered
normal. This does not indicate a problem exists or that a
higher
-octane fuel is necessary.
Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers' Association for better
vehicle performance and engine protection. Gasolines
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasolines.

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.

6-5
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don't use fuel containing
methanol. 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.
Filling Your Tank (Gasoline Engine)
CAUTION:
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.
If your vehicle has a diesel engine, see ªFilling Your
Tank (Diesel Engine)º in the Diesel Engine Supplement.

6-7
When you put the fuel 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 ªMalfunction Indicator Lampº in
the Index.
NOTICE:
If you need a new fuel 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 may damage your fuel tank and
emissions system. See ªMalfunction Indicator
Lampº in the Index.
Filling a Portable Fuel Container
CAUTION:
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.

Bring the fill nozzle in contact with the
inside of the fill opening before operating
the nozzle. Contact should be maintained
until the filling is complete.

Don't smoke while pumping gasoline.

6-59
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, GM 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.

6-69
Capacities and Specifications
All capacities are approximate. When adding, be sure to fill to the appropriate level or as recommended in
this manual.
See refrigerant charge label under the hood for charge capacity information and requirements.
Engine Identification -- Gasoline Engines
Engine ªVORTECº 4300 ªVORTECº 5000 ªVORTECº 5700 ªVORTECº 8100
Type V6 V8 V8 V8
VIN Code W M R G
Fuel System CSFI
1CSFI1CSFI1MFI2
Spark
Plug Gap0.060 inches
(1.52 mm)0.060 inches
(1.52 mm)0.060 inches
(1.52 mm)0.060 inches
(1.52 mm)
Firing Order
1
-6-5-4-3-21-8-4-3-6-5-7-21-8-4-3-6-5-7-21-8-7-2-6-5-4-3
1Central Sequential Fuel Injection
2Sequential Fuel Injection

6-71 Fuel Tank Capacity
TYPE QUANTITY MODEL TYPE
Standard Tank 31.0 U.S. gallons (117.3 L) Passenger and Cargo
Standard Tank 35.0 U.S. gallons (132.5 L) Cab and Chassis
Optional Tank* 55.0 U.S. gallons (208.1 L) Cab and Chassis
*159 inch wheelbase or 177 inch wheelbase only
Air Conditioning Refrigerant Capacity
If you do your own service work, you'll need the proper service manual. See ªDoing Your Own Service Workº in the
Index for additional information. It is recommended that service work on your air conditioning system be performed
by a qualified technician.
REFRIGERANT TYPE CAPACITY
R±134a 2.0 lbs. (0.91 kg)
Front
R±134a 3.5 lbs. (1.6 kg)
Front and Rear

Scheduled Maintenance
7-6
Short Trip/City Intervals
Every 24,000 Miles (40 000 km): Diesel Engine Only:
Fuel Cap Replacement, if driving in dusty conditions.
Every 30,000 Miles (50 000 km): Diesel Engine
Only: Engine Air Cleaner Filter Replacement.
Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over 8600 GVWR
or driven under severe conditions or equipped with
diesel engine).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. If Equipped: Exhaust Gas
Recirculation System Inspection. Gasoline Engine
Only: Evaporative Control System Inspection. Diesel
Engine Only: Crankcase Depression Regulator Valve
(CDRV) System Check.
Short Trip/City Intervals
Every 100,000 Miles (166 000 km): Gasoline Engine
Only: Spark Plug Wire Inspection. Gasoline Engine
Only: Spark Plug Replacement. Gasoline Engine
Only: Automatic Transmission Service (normal
conditions). Gasoline Engine Only (Except 8.1L V8):
Positive Crankcase Ventilation (PCV)
Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every 60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.

Scheduled Maintenance
7-8
Long Trip/Highway Intervals
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Diesel Engine Only: Engine Air
Cleaner Filter Replacement. Front Wheel Bearing
Repack (or at each brake relining, whichever
occurs first).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over 8600 GVWR
or driven under severe conditions or equipped with
diesel engine).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. If Equipped: Exhaust Gas
Recirculation System Inspection. Gasoline Engine
Only: Evaporative Control System Inspection. Diesel
Engine Only: Crankcase Depression Regulator Valve
(CDRV) System Check.
Long Trip/Highway Intervals
Every 100,000 Miles (166 000 km): Gasoline Engine
Only: Spark Plug Wire Inspection. Gasoline Engine
Only: Spark Plug Replacement. Gasoline Engine
Only: Automatic Transmission Service (normal
conditions). Gasoline Engine Only (Except 8.1L V8):
Positive Crankcase Ventilation (PCV)
Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every 60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.

Short Trip/City Scheduled Maintenance
7-23

Gasoline Engine Only: Conduct evaporative control system inspection. Check
all fuel and vapor lines and hoses for proper hook
-up, routing and condition.
Check that the purge valve works properly (if equipped). Replace as needed.
An Emission Control Service. (See footnote
.)
Diesel Engine Only: Replace engine air cleaner filter.
An Emission Control Service.
Gasoline Engine Only: See ªEngine Air Cleaner Filter Restriction Indicator
Checkº in the Index.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
Diesel Engine Only: Check the air intake system installation to assure that
gaskets are properly sealed and that all hose connections, fasteners and other
components are tight. Also check to be sure that the air cleaner housing is
properly seated and the cover fits tightly. Tighten connections and fasteners or
replace damaged parts as necessary. This is a Noise Emission Control Service.
Applicable only to vehicles sold in the United States.
Diesel Engine Only: If your engine has a thermostatically controlled cooling fan,
inspect all hoses and ducts for proper hook
-up (or every 12 months, whichever
occurs first). Be sure the valve works properly. This is a Noise Emission Control
Service. Applicable only to vehicles sold in the United States.
Diesel Engine Only: Check the crankcase depression regulator valve
system for any worn, plugged or collapsed hoses. See service manual.
An Emission Control Service.