1996 CHEVROLET SUBURBAN check engine light

Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are especially
important
in trailer operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system, an\
d brake
adjustment. Each
of these is covered in this manual, and the Index will help
you find them quickly. If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see
that all hitch nuts and bolts are tight.
Trailer Lighting Systems Wiring
See “Trailer Wiring Harness” in the Index.
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Turn off the ignition on both vehicles. Turn off all lights that aren’t
needed, and radios. This will avoid sparks and help save both batteries.
And it could
save your radio!
I NOTICE:
If you leave your radio on, it could be badly damaged. The
repairs wouldn’t be covered by your warranty.
Open the hoods and locate the batteries. Find the positive (+) and
negative
(-) terminals on each battery.
Check that the jumper cables don’t have loose or missing insulation. If
they do, you could get a shock. The vehicles could be damaged, too.
Before
you connect the cables, here are some basic things you should
know. Positive
(+) will go to positive (+) and negative (-) will go to
negative (-) or a metal engine part. Don’t connect (+) to (-) or you’ll
get a short that would damage the battery and maybe other parts, too.
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You should ask your service station operators if their gasolines contain
deposit control additives and oxygenates, and
if they have been
reformulated
to reduce vehicle emissions.
Diesel Fuel Requirements and Fuel System
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you
to buy permits or pay special taxes.
Some
of these restrictions apply only to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions
in any state or province, contact your auto club, the police or
other officials.
Fuel Requirements
NOTICE:
Diesel fuel or fuel additives not recommended in this manual
could damage your fuel system and engine. Your warranty
wouldn’t cover this damage. And:
Diesel fuel that has been mixed with engine oil could damage
your engine and emission controls.
Always check with your
service station operator to make sure his diesel fuel has not \
been mixed with engine oil.
If you ever run out of diesel fuel, it can be difficult to restart
your engine. “Running Out
of Fuel,” later in this section, tells
you how to get it started again.
To avoid all this, try never to
let your tank get empty.
What Fuel to Use
For best results, use Number 2-D diesel fuel year-round (above and below
freezing conditions) as
oil companies blend Number 2-D fuel to address
climate differences. Number 1-D diesel fuel may be used
in very cold
temperatures (when it stays below
0°F or -1 8°C); however, it will produce
a power and fuel economy
loss. The use of Number 1-D diesel fuel in warm
or hot climates may result in stalling, poor starting when the engine
is hot
and may damage the fuel injection system.
Diesel fuel may foam when you fill your tank. This can cause the automatic
pump nozzle
to shut off, even though your tank isn’t full. If this happens,
just wait for the foaming
to stop and then continue to fill your tank.
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If this happens, a WATER IN FUEL light will come
water must be drained. Your Cfpder can show you
hc
I
WATER
IN
FUEL
If the light comes on at any other time, use this chart.
! on. If it does, the excess
3w to do this.
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.
NOTICE:
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.
“WATER IN FUEL” LIGHT CHART Problem
Light comes on intermittently.
Light stays on:
Recommended Action
Drain water from fuel filter.
1. At temperatures above freezing. Drain fuel filter immediately. If no
water can be drained and light stays
on, see your dealer for assistance.
2. At temperatures below freezing. 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
filter.
3. Immediately after refueling -
large amount of water possibly
pumped into fuel tank. Fuel tank
purging required. See
your dealer for assistance.
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How to Check Lubricant
P
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant.
If the differential is at operating temperature (warm), add enough lubricant
to raise the level to the bottom of the filler plug hole.
If the differential is cold, add enough lubricant to raise the level to 1/2 inch
(I 2 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use
Use a mixture of one-half chi? wcmr (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
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Adding Coolant - Diesel Engine
x " The coolant surge tank is located on
the
passenger side at the
rear corner of the
engine compartment.
To Check Coolant
A CAUTION:
lbrning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow \
out
and burn you badly. Never turn the surge tank pressure
cap -
even a little - when the engine and radiator are hot.
When your engine is cold, the coolant level should be at the COLD mark. or
a little higher.
If this light comes on, it means you're low on engine coolant.
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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 GM 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 GM 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:
carry passengers and cargo within recommended limits. You will find
these limits on your vehicle’s CertificatiodTire label. See “Loading
Your Vehicle”
in the Index.
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.
use the recommended unleaded fuel. See “Fuel” in the Index.
Selecting the Right Schedule
The proper maintenance schedule for your vehicle depends on which engine
you have in your vehicle and how you use your vehicle.
Gasoline engine vehicles and diesel engine vehicles have different
maintenance requirements. If you have a diesel engine, follow
a schedule
designated for diesel engine vehicles
only. If you have a gasoline engine,
you must first determine whether your engine has a light duty or a heavy
duty emissions classification. Follow a maintenance schedule designated for
gasoline engines with the emissions classification (light duty or heavy duty)
for your engine. See “Engine Identification”
in the Index to find your
engine’s emission classification.
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Every 30,000 Miles (50 000 km)
Air Cleaner Filter Replacement
Spark Plug Replacement
Fuel Filter Replacement
Cooling System Service (or every
24 months, whichever occurs first)
Every 50,000 Miles (83 000 km)
Automatic Transmission Service (severe conditions only)
Every 60,000 Miles (100 000 km)
Engine Accessory Drive Belt Inspection
Spark Plug Wire Inspection
Engine Timing Check Fuel Tdnk, Cap and Lines Inspection
I
Schedule lI Definition - Gasoline Engines With Light Duty
Emissions
Follow Schedule 11 orzly if none of the conditions from Schedule I is true.
Every 7,500 Miles (12 500 km)
Engine Oil and Filter Change (or every 12 months, whichever occurs first)
Chassis Lubrication (or every
12 months, whichever occurs first)
Drive
Axle Service
At 7,500 Miles (12 500 km) - Then Every 15,000 Miles (25 000 km)
Tire Rotation
7-S
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