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Fuel
3800 (L27) Engine
The 8th digit of your Vehicle Identification Number
(VIN) shows the code letter for
your engine. You will
find the VIN at the top left of your instrument panel.
(See “Vehicle Identification Number’’ in the Index.)
Use regular unleaded gasoline rated at 87 octane or
higher. It should meet specifications ASTM D48
14 in
the
U.S. 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 gasoline (unleaded). You’ll see
“UNLEADED” right
on the pump. And only unleaded
nozzles will fit into your vehicle’s filler neck.
Be sure the posted octane is at least 87.
If the octane is
less than 87,
you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and
you
still hear heavy knocking, your engine needs service.
But don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a hill. That’s normal, and
you don’t have to buy a higher octane
fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
What about gasoline with blending materials that
contain oxygen (oxygenates), such
as MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.” Fuel that
is no
more than
15% MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended
fuel
that is no more than 10% ethanol is fine for your vehicle.
Methanol is methyl or wood alcohol.
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 “cosolvents” and
corrosion preventers in this fuel to help avoid
these problems.
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ProCarManuals.com
Page 232 of 324

Gasolines for Cleaner Air
Your use of gasoline with deposit control 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 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 deposit control additives and
oxygenates, and if they have been reformulated to
reduce vehicle emissions.
Fuel
3800 Supercharged (L67) Engine
The 8th digit of your Vehicle Identification Number
(VIN) shows the code letter for your engine. You will
find the VIN at the top left of your instrument panel.
(See “Vehicle Identification Number”
in the Index.)
Use premium unleaded gasoline rated at 91 octane or
higher.
You may use middle grade or regular unleaded
gasolines, but your vehicle may not accelerate as well.
The gasoline you use should meet specifications ASTM
D48 14 in the U.S. 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 gasoline (unleaded). You’ll see
“UNLEADED” right on the pump. And only unleaded
nozzles
will fit into your vehicle’s’filler neck.
Be sure the posted octane for premium is at least 91 (at
least 89 for middle grade and 87 for regular). If the
octane is less than 87, you may get a heavy knocking
noise when you drive. If it’s bad enough,
it can damage
your engine.
If you’re using fuel rated at 91 octane or higher and you
still hear heavy knocking, your engine needs service.
230
ProCarManuals.com
Page 233 of 324

But don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a hill. That’s normal
and you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
What about gasoline with blending materials that
contain oxygen (oxygenates), such as MTBE
or alcohol?
MTBE is “methyl tertiary-butyl ether.’’
Fuel that is no
more than
15% MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel
that is no more than
10% ethanol is fine for your vehicle.
Methanol is methyl or wood alcohol.
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 “cosolvents” and
corrosion preventers in this fuel to help avoid
these problems.
Gasolines for Cleaner Air
Your use of gasoline with deposit control 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 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 deposit control additives and
oxygenates, and if they have been reformulated to
reduce vehicle emissions.
231
ProCarManuals.com