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Downloaded from www.Manualslib.com manuals search engine r
P
A CAUTION
You can be iqjnred if you try to do service work on a vehicle
without knowing enough about it.
Be sure you have sdlicient knowledge, experience, and the
proper replacement parts and tools before you attempt any
vehicle maintenance task,
@ Be sure to use the proper nuts, bolts and other fasteners.
“k@sh” and ccmetricm fasteners can be easily eonffrsed. If
you use the mng fasteners, parts can later break or fall off.
You could be hurt.
1_ FUEL
!-
Use premium unleaded gasoline rated at 91 octane or higher. It should
meet specifications
ASTM D4814 in the US. and CGSB 3.5-92 in
Canada. These fuels should have the proper additives,
so you should not
have to add anything to the fuel.
In the U.S. and Canada, it’s easy to be sure you get the right kind of
only unleaded nozzles will fit into your vehicle’s filler neck.
T- gasoline (unleaded). You’ll see “UNLEADED” right on the pump. And
Be sure the posted octane is at least 91.
If the octane is less than 91, you
may get a heavy knocking noise when you drive. (In an emergency, you
may be able to use lower octane
-- as low as 87 -- if heavy knocking does
not occur.)
If you’re using 91 or higher octane unleaded gas and you still
get heavy knocking, your engine needs service.
I
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Downloaded from www.Manualslib.com manuals search engine What about gasoline with blending materials that contain oxygen, such as
MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.” Fuel that is no more than
15%
MTBE is fine for your car.
Ethanol is ethyl or grain alcohol. Properly-blended fuel that is no more
than
10% ethanol is fine for your car.
Methanol
is methyl or wood alcohol.
r 1
NOTICE:
Fuel that is more than 5% methanol is bad for your vehicle.
Don’t use it. 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. And even at
5% or less, there must
be 6Ccosolvents” and corrosion preventers in this fuel to help
avoid these Droblems.
Gasolines for Cleaner Air
Your use
of gasoline with detergent additives will help prevent deposits
from forming in your engine and fuel system. That helps keep your
engine
in tune and your emission control system working properly. It’s
good for your vehicle, and you’ll be doing your part for cleaner air.
Many gasolines are now blended with materials called oxygenates.
General Motors recommends that you use gasolines
with these blending
materials, such as
MTBE and ethanol. By doing so, you can help clean
the air, especially in those parts
of the country that have high carbon
monoxide levels.
In addition, some gasoline suppliers are now producing reformulated
gasolines. These gasolines are specially designed to reduce vehicle
emissions. General Motors recommends that you use reformulated
gasoline. By doing
so, you can help clean the air, especially in those parts
of the country that have high ozone levels.
You should ask your service station operators if their gasolines contain
detergents and oxygenates, and
if they have been reformulated to reduce
vehicle emissions.
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Downloaded from www.Manualslib.com manuals search engine Oils with these words on the container will help you save fuel.
This doughnut-shaped logo (symbol) is used on most oil containers
to
help you select the correct oil.
You should look for this on the oil container, and use only those oils that
display the logo.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the
requirements for your vehicle.
Engine Oil Additives: Don’t add anything to your oil. Your Cadillac
dealer is ready to advise
if you think something should be added.
When to Change Engine Oil: Your vehicle is equipped with an engine oil
life index (EOLI) feature as part
of the Driver Information Center
display (DIC). Oil change intervals are determined by the EOLI and will
usually fall at, or between, the
two recommended alternative intervals of
3,000 miles (5,000 kilometers) and 7,500 miles (12,500 kilometers), but
could be shorter than
3,000 miles (5,000 kilometers) under some very
severe driving conditions shown in Schedule I. The system will also
indicate the need for an oil change if
7,500 miles (12,500 kilometers) or
one year has passed.
Engine
oil life remaining is displayed through engine data as the ‘OIL
LIFE INDEX’ and as a ‘CHANGE ENGINE OIC message. The
‘OIL
LIFE INDEX’ display includes a number between 0 and 100. This is the
percentage
of oil life REMAINING based on driving conditions and
mileage driven since the last time of the oil life indicator was reset. When
the remaining oil life is less than
lo%, a ‘CHANGE OIL SOON’ message
will appear. This is a reminder to schedule an engine oil change. When
the oil life index reaches
0, the ‘CHANGE ENGINE OIC message will
appear. This indicates that no oil life remains and the oil should be
changed
as soon as possible, but certainly within the next 200 miles (320
km).
The EOLI will not detect excessively dusty conditions or engine
malfunctions which may effect the
oil. If you drive in dusty areas, change
the engine oil after every
3,000 miles (5,000 kilometers) or 3 months
(whichever comes first), unless instructed to do
so sooner by the DIC.
xu -
On Northstar 4.6 Liter engine equipped vehicles a ‘CHECK OIL LEVEE
message will appear whenever the oil level’s approximately one quart low.
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