1999 GMC C-SERIES fuel pressure

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v
For example,
these symbols
are used on an
original battery:
CAUTION
POSSIBLE
INJURY
PROTECT
EYES BY
SHIELDING
CAUSTIC
BATTERY
ACID COULD
CAUSE
BURNS
AVOID
SPARKS OR
FLAMES
SPARK OR
FLAME
COULD
EXPLODE
BATTERY
These symbols
are important
for you and
your passengers
whenever your
vehicle is
driven:
DOOR LOCK
UNLOCK
FASTEN
SEAT
BELTS
POWER
WINDOW
AIR BAG
These symbols
have to do with
your lamps:
MASTER
LIGHTING
SWITCH
TURN
SIGNALS
PARKING
LAMPS
HAZARD
WARNING
FLASHER
DAYTIME
RUNNING
LAMPS
FOG LAMPS
These symbols
are on some of
your controls:
WINDSHIELD
WIPER
WINDSHIELD
WASHER
WINDSHIELD
DEFROSTER
REAR
WINDOW
DEFOGGER
VENTILATING
FAN
These symbols
are used on
warning and
indicator lights:
ENGINE
COOLANT
TEMP
BATTERY
CHARGING
SYSTEM
BRAKE
COOLANT
ENGINE OIL
PRESSURE
ANTI-LOCK
BRAKES
Here are some
other symbols
you may see:
FUSE
LIGHTER
HORN
SPEAKER
FUEL
Vehicle Symbols
These are some of the symbols you may find on your vehicle.
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2-65
This light should come on when the ignition is on, but
the engine is not running, as a check to show you it is
working. If it does not come on at all, have it repaired.
NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be as
good and your engine may not run as smoothly.
This could lead to costly repairs that may not be
covered by your warranty.
Engine Oil Pressure Gage
Gasoline Engine Diesel Engine
The engine oil pressure gage, on the lower right portion
of your instrument cluster, shows engine oil pressure
in psi (pounds per square inch) or in kPa (kilopascals).
Oil pressure may vary with outside temperature and oil
viscosity, but readings of 30 to 40 psi (205 to 275 kPa)
on gasoline engines at operating temperature and
moderate road speeds are normal. If you have a diesel
engine, the normal operating range should be between
35 and 70 psi (240 to 480 kPa).
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4-28
If you have a diesel engine, you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start the engine again and repeat this only
when you feel really uncomfortable from the cold. But
do it as little as possible. Preserve the fuel as long as you
can. To help keep warm, you can get out of the vehicle
and do some fairly vigorous exercises every half hour or
so until help comes.Loading Your Vehicle
The GVW/Tire Information label is found on the rear
edge of the driver's door. The label shows the size of
your original tires and the inflation pressures needed to
obtain the gross weight capacity of your vehicle.
This is called the Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight of the
vehicle, all occupants, fuel and cargo.
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5-33
5. Then replace the pressure cap. Be sure the arrows on
the pressure cap line up like this.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This
improves fuel economy and reduces fan noise. Under
heavy vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
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6-
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Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-4 Fuel (Gasoline Engine)
6
-5 Diesel Fuel Requirements and Fuel System
6
-6 Fuels in Foreign Countries (Gasoline Engines)
6
-7 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-9 Checking Things Under the Hood
6
-11 Noise Control System
6
-13 Engine Oil (Gasoline Engine)
6
-17 Engine Oil (Caterpillar
Diesel Engine)
6
-17 Engine Air Cleaner/Filter
6
-18 Automatic Transmission Fluid
6
-19 Manual Transmission Fluid
6
-20 Rear Axle
6
-20 Rear Axle Shift Motor (Option)
6
-21 Radiator Pressure Cap (Gasoline Engines)
6
-22 Surge Tank Pressure Cap (Diesel Engines)
6
-22 Thermostat6
-23 Engine Coolant (Gasoline Engine)
6
-27 Engine Coolant (Caterpillar
Diesel Engine)
6
-28 Power Steering Fluid
6
-29 Windshield Washer Fluid
6
-30 Brakes
6
-36 Electric/Hydraulic Parking Brake Fluid
6
-42 Battery
6
-44 Other Service Items
6
-48 Tires
6
-59 Appearance Care
6
-59 Cleaning the Inside of Your Vehicle
6
-63 Cleaning the Outside Your Vehicle
6
-66 GM Vehicle Care/Appearance Materials
6
-67 Vehicle Identification Number (VIN)
6
-67 Service Parts Identification Label
6
-68 Electrical System
6
-74 Capacities and Specifications
6
-77 Air Conditioning Refrigerants
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6-49 Inflation -- Tire Pressure
The Certification/Tire label, which is on the driver's
door, shows the correct inflation pressures for your tires
when they're cold. ªColdº 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)
NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:

Unusual wear

Bad handling

Rough ride

Needless damage from road hazards.
When to Check
Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check
Use a good quality pocket
-type gage to check tire
pressure. You can't tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they're underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt
and moisture.
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6-77
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same.
If the air conditioning system in your vehicle needs
refrigerant, be sure the proper refrigerant is used.
If you're not sure, ask your dealer.
Air Conditioning Refrigerant Capacity
Refrigerant R-134a 2.5 lbs. (1.134 kg). . . . . . . . . . . .
This capacity (volume) is approximate.
Normal Maintenance Replacement
Parts
Allison Transmission External Filters
Engine GM (AC) Part Number
7.2L 25011122 (PF897). . . . . . . . . . . . . . . . . . . . . . .
7.4L 25011122 (PF897). . . . . . . . . . . . . . . . . . . . . . .
Air Compressor Filter
Air Compressor GM Part Number
Bendix Tu
-Flo
550 (13.2 CFM)2467368
Service Replacement Part and
Filter Recommendations
Engine 7.2L 7.4L
RPO LG5 LP4/L21
Spark Plug Ð AC Type R41
-932
ÐGap Ð 0.060 inch
(1.52 mm)
ÐTorque Ð 22.0 lb. ft.
(30.0 Nm)
Oil Filter CAT

2P4004 AC Type PF-932
PCV Valve Ð AC Type CV
-774C
Air Cleaner* Donaldson
P522606Donaldson
P533355
Fuel Filter AC
-TP-915 Pri-
mary**AC Type GF-481
Pressure Caps RC
-54 Ð
*Optional Davco (K28) D350921 spin
-on type filter
located in component box.
**Optional Cold Weather (KUK) Racor B6484GM
spin
-on type located in component box. Optional Davco
heated fuel water separator mounted on the side of the
diesel engine.
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7-21
(25) = Check thermostatically controlled air cleaner
installation to make certain that all ducts are connected and
correctly installed. Also, check valve for proper operation.
(26) = Evaporative Control System Service (if equipped):
Check all fuel and vapor lines and hoses for proper
connections and correct routing (or every 24 months,
whichever occurs first). Replace parts as needed.
(27) = Replace air cleaner filter (or every 24 months,
whichever occurs first). Replace filter more often if
driving in dusty conditions. Ask your dealer for the
proper replacement intervals for your driving conditions.
(28) = Replace spark plugs. Inspect wires for damage.
Check the wire boot and boot heat shield fit at spark
plugs and coil. Replace parts as needed.
(30) = Check the fuel tank, fuel cap and fuel lines for
damage which could cause leakage. Inspect fuel cap for
correct sealing ability and any indications of damage.
Check fuel cap gasket for even filler neck imprint.
Replace parts as needed.
(31) = Check EGR system as described in the service
manual. See ªService and Owner Publicationsº in the Index.
(32) = Inspect Electronic Vacuum Regulator Valve
(EVRV) filter for excessive contamination or plugging.
If needed, clean filter with solution of soap and water,
let dry and install.(33) = Check the PCV system for proper operation and
clean PCV valve. Replace hoses as needed.
(34) = Replace PCV valve and blow out the PCV valve
hose with compressed air. Replace hoses as needed.
(35) = Drain, flush and refill cooling system. See
ªRecommended Fluids and Lubricantsº in the Index for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap and neck. Pressure test cooling system and
pressure cap. For Caterpillar
 diesel engines, always refer
to the Caterpillar Diesel Engine Operation & Maintenance
Manual for coolant recommendations and change intervals.
(37) = Rear axle service: Change the lubricant. See
ªRecommended Fluids and Lubricantsº in the Index.
(38) = Front axle service: Re
-pack upper kingpin
roller bearing.
(39) = Air brake service:

Inspect brake lines and hoses for proper hook
-up,
binding, leaks, cracks, chafing, etc. Inspect drum
brake linings for wear or cracks. Inspect other brake
parts at each wheel, including drums, wheel cylinders
and piston heat shields and boots. Check brake pedal
for excessive free play or travel (or every 6 months,
whichever occurs first) and have serviced if needed.
Check brakes more often if driving habits and
conditions result in frequent braking.
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