1994 CHEVROLET SUBURBAN air filter

Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen if a service station doesn’t regularly inspect and clean
its fuel tanks, or if it gets contaminated fuel from its suppliers.
If this happens, a “WATER IN FUEL” light will come on. If it does, the
excess water
must be drained. Your dealer can do this for you.
This light
also should come on briefly when you start your engine, as a
check. If it doesn’t, have it fixed so it will be there to let you know if you
ever do get water
in your fuel.
If the light comes on at any other time, use this chart.
“WATER IN FUEL” LIGHT CHART
Problem
Light comes on intermittently.
Light stays on:
1. At temperatures above
freezing.
2. At temperatures below
freezing.
Recommended Action
Drain water from fuel filter.
Drain fuel filter immediately.
If no
water can be drained and light stays
on, see your dealer for assistance.
Drain fuel filter immediately. If no
water can be drained
- water may
be frozen. Open
the air bleed valve
to check for
fuel pressure. If no fuel
pressure
is present, replace the fuel
fi 1 ter.
3. Immediately after refueling - Fuel tank purging required. See
large amount
of water possibly your dealer for assistance.
pumped into fuel tank.
Hesitation or “flat” performance at
high speed or during hard acceleration
may be an indication of premature fuel filter plugging due to dirty or
contaminated
fuel. The filter element may need to be changed if this
happens. See your dealer for assistance.
If you drive when this warning light is on, you can damage your
fuel injection system and your engine.
If the light comes on right
after you refuel,
it means water was pumped into your fuel tank.
Turn
off your engine immediately. Then, have the water drained
at once.
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NOTICE:
If there is water in your diesel fuel and the weather is warm or
humid, fungus and bacteria can grow in the fuel. They can
damage your fuel system. You’ll need a diesel fuel biocide
to
sterilize your fuel system. Your dealer can advise you if you ever
need this.
If your fuel tank needs to be purged to remove water, see your
dealer or
a qualified technician. Improper purging can damage
your fuel system.
Running Out of Fuel (Diesel Engines)
If the engine stalls and you think that you’ve run out of fuel, do this:
First, open the fuel
filter air bleed valve.
If there is air, then
you
are probably out of
fuel.
To restart your engine:
1. If you’re parked on a level surface, add at least two gallons of fuel.
However, if you’re parked
on a slope, you may need to add up to five
gallons
of fuel.
10 to 15 seconds to crank (but not start) your engine. Keep doing this
until
you can just see some clear fuel at the air bleed valve. (If, during
this step, the engine starts, turn the ignition off and close the valve
before restart.)
2. With the air bleed valve open, turn your ignition key to “Start” for
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3. Close the air bleed valve.
4. Turn the ignition key to “Start” for 10 to 15 seconas at a time until your
engine starts.
Fuel Filter Replacement (Diesel Engines)
If you want to change the fuel filter yourself, here’s how to do it:
Drain fuel from the filter by opening the air bleed valve and the water drain
valve. This prevents the
fuel from spilling as you replace the filter. Drain the
fuel into a fuel-resistant container and dispose
of it properly.
1. Turn off the engine and apply the parking brake.
2. Take off the fuel tank cap. This releases vacuum in the tank.
3. The filter is located at the rear of the intake manifold.
4;: .
4. Unscrew and
remove the ring
nut from the top
of the filter head.
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8.
9.
10.
5. Lift the element out of the filter
head.
6. If there is any dirt
on the element
sealing surface of
the filter head,
clean it off.
7. Line up the
writing
on the top
of the filter
so it
faces (is readable
from) the front of
the vehicle.
Push
the element in
until the mating
surfaces touch.
With the air bleed valve open, turn your ignition key to
RUN for 10 to
15 seconds. Wait one minute for your starter to cool.
Do this until you
can see clear fuel coming from the air bleed valve.
Close the air bleed valve and replace the fuel cap.
Start your engine and let it idle for five minutes. Check your fuel filter
and air bleed valve for leaks.
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Air Cleaner
Refer to the
Maintenance Schedule to determine when to
replace the air filter.
See “Scheduled
Maintenance Services” in the Index.
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 d\
amage it. Always have the air cleaner in place when you’re drivin\
g.
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To remove the air
cleaner filter
on a gas
engine or
a 6.5 liter
naturally aspirated
diesel, turn the wing
nuts
to the left.
Remove the cover and
change the filter.
To remove the air cleaner filter on a 6.5 liter turbocharged diesel, first
remove the rubber elbow. Remember to observe the caution about
turbocharger blades on the rubber elbow,
Then, unhook the
cover retaining clips
and push the rear
of
the cover toward the
engine.
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. Refer to the Maintenance Schedule to determine
when to change your fluid.
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 a
GM dealership Service Department.
If you do it yourself, be sure to follow all the instructions here, or you could
get
a false reading on the dipstick.
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Service Replacement Part and Filter
Recommendations -Gas Engines
Engine
VIN
Oil Filter
Air Cleaner Filter
PCV Valve
Spark Plugs‘%
Fuel Filter
Radiator Cap
5.7L
K
PF353‘
A348C
cv774c
.CR43TS
GF48 1
RC36
$Four Wheel Drive Vehicle -use a
PFS 1 oil filter
*Use AC copper-cored resister type spark plugs
Service Replacement Part and Filter
Recommendations -Diesel Engines
Engine
VIN
Oil Filter
Air Cleaner
Fuel Filter
Surge Tank Cap 6.5L
S”
PF3S
A917C
TP
I 006
RC33
7.4L
N
PF35
A348C
cv774c
.CR43TS
GF48
I
RC36
6.5L
F”
PF35
A9 17C
TP
1006
RC33
*Heavy Duty Emission Engine
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 GM dealer. For additional information, see
your “Warranty and Owner Assistance Information” booklet.
Air Conditioning Refrigerant Capacity
TYPE
Refrigerant R 134A
Refrigerant
R 134A
QTY
Front A/C 3.0 lbs. (1.360 kg)
Front and Rear A/C
4.25 Ibs. (I .927 kg)
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GASOLINE ENGINES WITH HEAVY DUTY EMISSIONS
- MAINTENANCE SCHEDULE yf
Item Miles (000) 3
No. Kilometers (000) 5 Service
I
1 Engine Oil Change*-Every 3 Months, or t
Oil Filter Change*-Every 3 Months, or t
12 Chassis Lubrication-Every 12 Months, or I+
II
3 Clutch Fork Ball Stud Lubrication (5-speed manual
transmission with deeplow only)
Cooling System Service*-Every 24 Months or
Air Cleaner Filter Replacement* Front Wheel Bearing Repack
Transmission Service
**
Fuel Filter Replacement*
10
11
12
13
14
15
16
17
18
I9
Spark Plugs Replacement*
Spark Plug Wire Inspection*
EGR System Inspection*
Electronic Vacuum Regulator Valve (EVRV)
Inspection*
Engine Timing Checkk
Fuel Tank, Cap and Lines Inspection
*
Thermostatically Controlled Air Cleaner
Inspectionk
Engine Accessory Drive (Serpentine) Belt
Inspection*
Evaporative Control System Inspection*
Shields and Underhood Insulation InspectionA.
20
21
-
23
24
-
Air Intake System InspectionA. I
Brake Systems Inspection** I
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in the Index.
A A Noise Emission Control Service
Applicable only to vehicles sold in the United States
t To determine the emissions classification of your engine, refer to “Selecting the Proper
Maintenance Chart” in this section.
TO404
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